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University of Michigan
1.
Natarajan, Vinod Kumar.
Spark -assisted compression ignition: An experimental investigation into how spark ignition advances combustion phasing in gasoline HCCI engines.
Degree: PhD, Mechanical engineering, 2006, University of Michigan
URL: http://hdl.handle.net/2027.42/126242 
► Implementation of homogeneous charge compression ignition (HCCI) combustion in gasoline engines, while operating with improved fuel economy and reduced NOx emissions, is limited by the…
(more)
▼ Implementation of homogeneous charge
compression ignition (HCCI)
combustion in gasoline engines, while operating with improved fuel economy and reduced NOx emissions, is limited by the inability to control
combustion phasing.
Spark-
assisted compression ignition (SACI) is a mechanism that controls HCCI
combustion phasing, using
spark ignition to advance the onset of
compression ignition (CI). SACI was employed at two light-load operating points (200 kPa and 300 kPa IMEP at fueling rates of 7 and 10 mg per cycle, respectively) to advance the phasing of a marginally-stable HCCI operating point. At the lower load, stratification by means of direct injection of 3 mg fuel at the time of
spark ignition was required to advance phasing using SACI. At the higher load, robust SACI operation required less stratification (late injection of 1 mg). NOx emissions increased two- and four-fold in SACI relative to HCCI operation at the lower and higher load, respectively; this increase was shown to result primarily from the stratification. This study identified two issues confounding SACI, only observed at the lower load: cyclic variability in CI
combustion phasing and inability to sufficiently advance phasing. To address these issues, new metrics were created in this study to identify four stages of the SACI
combustion process:
spark discharge, early kernel growth (EKG), flame propagation, and CI. Experiments were performed using an optical HCCI engine to simultaneously acquire steady-state emissions, in-cylinder pressure data,
spark-discharge current and voltage waveforms, images of the plasma channel, and images of
combustion chemiluminescence from two orthogonal views at sub-crank-angle resolution; these measurements were used to identify the four stages for each engine cycle and thereby the cyclic variability of each stage. It was concluded that cyclic variability in the EKG, the period of low flame growth-rate and weak chemiluminescence, was the dominant cause of cyclic variability in
combustion phasing. Also, findings indicated only a weak correlation between the creation of large kernels and motion of the plasma channel away from the
spark gap. At the higher load, robust flame propagation immediately followed the
spark discharge. It was inferred that local fuel/air distribution affected the transition to flame propagation.
Advisors/Committee Members: Sick, Volker (advisor).
Subjects/Keywords: Advances; Combustion; Engines; Experimental; Gasoline; Hcci; Homogeneous Charge Compression Ignition; How; Investigation; Phasing; Spark Ignition; Spark-assisted Compression Ignition; Spark-ignition
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APA (6th Edition):
Natarajan, V. K. (2006). Spark -assisted compression ignition: An experimental investigation into how spark ignition advances combustion phasing in gasoline HCCI engines. (Doctoral Dissertation). University of Michigan. Retrieved from http://hdl.handle.net/2027.42/126242
Chicago Manual of Style (16th Edition):
Natarajan, Vinod Kumar. “Spark -assisted compression ignition: An experimental investigation into how spark ignition advances combustion phasing in gasoline HCCI engines.” 2006. Doctoral Dissertation, University of Michigan. Accessed April 13, 2021.
http://hdl.handle.net/2027.42/126242.
MLA Handbook (7th Edition):
Natarajan, Vinod Kumar. “Spark -assisted compression ignition: An experimental investigation into how spark ignition advances combustion phasing in gasoline HCCI engines.” 2006. Web. 13 Apr 2021.
Vancouver:
Natarajan VK. Spark -assisted compression ignition: An experimental investigation into how spark ignition advances combustion phasing in gasoline HCCI engines. [Internet] [Doctoral dissertation]. University of Michigan; 2006. [cited 2021 Apr 13].
Available from: http://hdl.handle.net/2027.42/126242.
Council of Science Editors:
Natarajan VK. Spark -assisted compression ignition: An experimental investigation into how spark ignition advances combustion phasing in gasoline HCCI engines. [Doctoral Dissertation]. University of Michigan; 2006. Available from: http://hdl.handle.net/2027.42/126242
University of Michigan
2.
Ortiz-Soto, Elliott Alexander.
Combustion Modeling of Spark Assisted Compression Ignition for Experimental Analysis and Engine System Simulations.
Degree: PhD, Mechanical Engineering, 2013, University of Michigan
URL: http://hdl.handle.net/2027.42/102314
► Advanced combustion strategies provide significant efficiency and emissions benefits compared to conventional spark ignited (SI) combustion, but challenges related to combustion control and load limits…
(more)
▼ Advanced
combustion strategies provide significant efficiency and emissions benefits compared to conventional
spark ignited (SI)
combustion, but challenges related to
combustion control and load limits have made these technologies difficult to implement in practical systems. Until now, low cost reduced order models necessary for large parametric and multi-cycle studies capable of accurately capturing the full range of
combustion modes from homogeneous charge
compression ignition (HCCI) and
spark-
assisted compression ignition (SACI) to SI have not been available. This important computational gap for advanced
combustion engine research was the primary motivation for this doctoral work. The outcomes of this study include powerful new tools to evaluate advanced
combustion strategies as well as novel methods to incorporate important advanced
combustion characteristics into reduced order models.
A reduced order thermodynamic model of advanced SACI
combustion was first proposed. The model was used with available experimental data and previous high fidelity simulation results to develop a new empirical auto-
ignition burn rate model that captures the effects of
ignition timing, composition, temperature, pressure, engine speed, stratification and flame propagation.
A complete engine model was then developed and incorporated into the commercial simulation software GT-Power. The model included chemical kinetics for low temperature heat release and auto-
ignition detection and the empirical burn rate model for post-
ignition heat release, as well as a new flame propagation model with improved physical groundings. The calibrated engine model showed good agreement with experimental trends of HCCI, SACI and SI
combustion modes.
The engine model was then used to assess practical strategies for accessing the advanced
combustion regime and improving engine efficiency. The results showed HCCI and SACI provide a pathway for significant efficiency benefits compared to throttled SI, with efficiency improvements between 15-25% across a range of loads from 1-7 bar BMEP. Further efficiency gains appear possible beyond the experimentally observed SACI limit.
As a further exercise, the load extension potential of boosted SACI
combustion was conceptually investigated using a simple thermodynamic framework incorporating the empirical burn rate model and practical operating constraints. The results indicate boosted SACI can nearly double the maximum engine load compared to naturally aspirated operation.
Advisors/Committee Members: Wooldridge, Margaret S. (committee member), Assanis, Dionissios N. (committee member), Fidkowski, Krzysztof J. (committee member), Martz, Jason Brian (committee member), Lavoie, George A. (committee member), Babajimopoulos, Aristotelis (committee member), Borgnakke, Claus (committee member).
Subjects/Keywords: Spark Assisted Compression Ignition, Saci; Homogeneous Charge Compression Ignition, Hcci, Spark Ignition, Si, Knock; Advanced Combustion Engines; Combustion Modeling; Engine Simulation; Efficiency, Fuel Economy, Load Extension, Load Expansion; Mechanical Engineering; Engineering
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APA ·
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APA (6th Edition):
Ortiz-Soto, E. A. (2013). Combustion Modeling of Spark Assisted Compression Ignition for Experimental Analysis and Engine System Simulations. (Doctoral Dissertation). University of Michigan. Retrieved from http://hdl.handle.net/2027.42/102314
Chicago Manual of Style (16th Edition):
Ortiz-Soto, Elliott Alexander. “Combustion Modeling of Spark Assisted Compression Ignition for Experimental Analysis and Engine System Simulations.” 2013. Doctoral Dissertation, University of Michigan. Accessed April 13, 2021.
http://hdl.handle.net/2027.42/102314.
MLA Handbook (7th Edition):
Ortiz-Soto, Elliott Alexander. “Combustion Modeling of Spark Assisted Compression Ignition for Experimental Analysis and Engine System Simulations.” 2013. Web. 13 Apr 2021.
Vancouver:
Ortiz-Soto EA. Combustion Modeling of Spark Assisted Compression Ignition for Experimental Analysis and Engine System Simulations. [Internet] [Doctoral dissertation]. University of Michigan; 2013. [cited 2021 Apr 13].
Available from: http://hdl.handle.net/2027.42/102314.
Council of Science Editors:
Ortiz-Soto EA. Combustion Modeling of Spark Assisted Compression Ignition for Experimental Analysis and Engine System Simulations. [Doctoral Dissertation]. University of Michigan; 2013. Available from: http://hdl.handle.net/2027.42/102314
3.
Middleton, Robert John.
Simulation of Spark Assisted Compression Ignition Combustion Under EGR Dilute Engine Operating Conditions.
Degree: PhD, Mechanical Engineering, 2014, University of Michigan
URL: http://hdl.handle.net/2027.42/107052
► Spark Assisted Compression Ignition (SACI) combustion has been shown to provide highly efficient, potentially low NOx operation similar to Homogeneous Charge Compression Ignition (HCCI) combustion.…
(more)
▼ Spark Assisted Compression Ignition (SACI)
combustion has been shown to provide highly efficient, potentially low NOx operation similar to Homogeneous Charge
Compression Ignition (HCCI)
combustion. Direct control over
ignition timing and burn rate through SACI operation has the ability to overcome shortcomings of HCCI operation allowing an increase in power density. Detailed SACI models capable of capturing the charge preparation process and impact of dilution method on
combustion are currently limited. The current work addresses this need by developing such a model and investigating SACI
combustion in an engine simulation.
Modeling requires valid predictions of laminar flame speeds under SACI conditions which are not available in the literature. To address this need under highly EGR dilute, high preheat temperature SACI conditions, laminar reaction front simulations were conducted. Moderate burning velocities were observed for EGR dilutions typical SACI operation, provided that preheat temperatures were elevated and burned gas temperatures exceeded 1450K. For a given preheat and burned gas temperature, EGR dilution suppressed burning velocities relative to air dilution, behavior attributed to decreases in mixture oxygen. Correlations of laminar burning velocity and thickness were developed from these data.
An existing model for HCCI, SI, and SACI
combustion in KIVA-3V was extended to capture engine breathing and charge preparation by direct injection under conditions utilizing EGR dilution. The model was capable of predicting trend-wise agreement with metal engine cylinder pressure measurements for HCCI, SI, and SACI
combustion.
Analysis showed that during SACI operation,
compression heating from reaction front heat release increased the end-gas temperature to initiate end-gas auto-
ignition, providing control over the
combustion process. Manipulation of the flame heat release by varying intake temperature,
spark timing, and dilution composition allowed control over heat release rates independent of
combustion phasing, reducing peak heat release rates while increasing load and efficiency. The influences on end-gas heat release rate were the total end-gas mass and the temperature stratification prior to auto-
ignition, which evolved significantly during the flame propagation phase. Insights from this work can be used to guide SACI operating strategies to enable high efficiency engine operation at higher power density than with HCCI
combustion.
Advisors/Committee Members: Assanis, Dionissios N. (committee member), Wooldridge, Margaret S. (committee member), Fidkowski, Krzysztof J. (committee member), Im, Hong (committee member), Martz, Jason Brian (committee member), Lavoie, George (committee member).
Subjects/Keywords: Combustion; Spark Assisted Compression Ignition; Mechanical Engineering; Engineering
…121
xiv
Abstract
Spark Assisted Compression Ignition (SACI) combustion has… …Spark Assisted Compression Ignition (SACI) is a method of triggering HCCI combustion… …Homogeneous Charge
Compression Ignition (HCCI) combustion. Direct control over ignition… …Assisted Compression Ignition (SACI), in an attempt to realize
the benefits of HCCI… …Compression Ignition (HCCI) is a combustion strategy that was
developed to address the…
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APA ·
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APA (6th Edition):
Middleton, R. J. (2014). Simulation of Spark Assisted Compression Ignition Combustion Under EGR Dilute Engine Operating Conditions. (Doctoral Dissertation). University of Michigan. Retrieved from http://hdl.handle.net/2027.42/107052
Chicago Manual of Style (16th Edition):
Middleton, Robert John. “Simulation of Spark Assisted Compression Ignition Combustion Under EGR Dilute Engine Operating Conditions.” 2014. Doctoral Dissertation, University of Michigan. Accessed April 13, 2021.
http://hdl.handle.net/2027.42/107052.
MLA Handbook (7th Edition):
Middleton, Robert John. “Simulation of Spark Assisted Compression Ignition Combustion Under EGR Dilute Engine Operating Conditions.” 2014. Web. 13 Apr 2021.
Vancouver:
Middleton RJ. Simulation of Spark Assisted Compression Ignition Combustion Under EGR Dilute Engine Operating Conditions. [Internet] [Doctoral dissertation]. University of Michigan; 2014. [cited 2021 Apr 13].
Available from: http://hdl.handle.net/2027.42/107052.
Council of Science Editors:
Middleton RJ. Simulation of Spark Assisted Compression Ignition Combustion Under EGR Dilute Engine Operating Conditions. [Doctoral Dissertation]. University of Michigan; 2014. Available from: http://hdl.handle.net/2027.42/107052
University of Michigan
4.
Martz, Jason Brian.
Simulation and Model Development for Auto-Ignition and Reaction Front Propagation in Low-Temperature High-Pressure Lean-Burn Engines.
Degree: PhD, Mechanical Engineering, 2010, University of Michigan
URL: http://hdl.handle.net/2027.42/78870
► While Homogeneous Charge Compression Ignition (HCCI) combustion is capable of highly efficient, ultra-low NOx operation, it lacks direct mechanisms for timing and burn rate control…
(more)
▼ While Homogeneous Charge
Compression Ignition (HCCI)
combustion is capable of highly efficient, ultra-low NOx operation, it lacks direct mechanisms for timing and burn rate control and suffers from marginal power densities. Concepts such as
Spark-
Assisted Compression Ignition (SACI)
combustion have shown the ability to partially address these shortcomings, however detailed SACI models are currently lacking.
To address the need for reaction front data within the ultra-dilute, high pressure and preheat temperature SACI regime, laminar premixed reaction front simulations were performed and correlations for burning velocity and front thickness were developed from the resulting dataset. Provided that preheat temperatures were elevated and that burned gas temperatures exceeded 1500 K, moderate burning velocities were observed at equivalence ratios typical of mid and high load HCCI operation. For a given burned gas temperature, burning velocities increased when moving from the SI to the SACI
combustion regime, i.e. towards higher dilution and higher pre-heat temperatures.
Given the proximity of SACI pre-heat temperatures to the
ignition temperature, additional simulations examined the
combustion regime, structure and general behavior of the reaction front as it propagated into an auto-igniting end-gas. While significant increases in burning velocity accompanied the transition from deflagrative to chemically dominated
combustion, the reaction front contributed minimally to end-gas consumption once end-gas temperatures exceeded 1100 K.
A model capable of capturing SI, SACI and HCCI
combustion modes was formulated and implemented into KIVA-3V. Using the correlated laminar flame speed data, the model was capable of predicting trend-wise agreement with cylinder pressure and imaging data from an optical SACI engine. The simulated presence of flame surface density suggests that although the simulated reaction fronts are ultra-dilute, they are nevertheless within the flamelet regime during the deflagration portion of SACI
combustion. End-gas auto-
ignition occurred when the charge
compression heating from boundary work and reaction front heat release combined to drive the end-gas to its
ignition temperature, providing additional latitude for the execution and control of low temperature
combustion processes. Additional simulations were performed to assess the ability of this additional deflagrative
combustion mode to enable high efficiency operation with elevated work output relative to HCCI
combustion.
Advisors/Committee Members: Assanis, Dionissios N. (committee member), Babajimopoulos, Aristotelis (committee member), Driscoll, James F. (committee member), Fiveland, Scott B. (committee member), Lavoie, George (committee member), Wooldridge, Margaret S. (committee member).
Subjects/Keywords: HCCI; Spark Assisted Compression Ignition; Knock; Low Temperature Combustion; Flamelet; Spark Ignited; Mechanical Engineering; Engineering
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APA ·
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APA (6th Edition):
Martz, J. B. (2010). Simulation and Model Development for Auto-Ignition and Reaction Front Propagation in Low-Temperature High-Pressure Lean-Burn Engines. (Doctoral Dissertation). University of Michigan. Retrieved from http://hdl.handle.net/2027.42/78870
Chicago Manual of Style (16th Edition):
Martz, Jason Brian. “Simulation and Model Development for Auto-Ignition and Reaction Front Propagation in Low-Temperature High-Pressure Lean-Burn Engines.” 2010. Doctoral Dissertation, University of Michigan. Accessed April 13, 2021.
http://hdl.handle.net/2027.42/78870.
MLA Handbook (7th Edition):
Martz, Jason Brian. “Simulation and Model Development for Auto-Ignition and Reaction Front Propagation in Low-Temperature High-Pressure Lean-Burn Engines.” 2010. Web. 13 Apr 2021.
Vancouver:
Martz JB. Simulation and Model Development for Auto-Ignition and Reaction Front Propagation in Low-Temperature High-Pressure Lean-Burn Engines. [Internet] [Doctoral dissertation]. University of Michigan; 2010. [cited 2021 Apr 13].
Available from: http://hdl.handle.net/2027.42/78870.
Council of Science Editors:
Martz JB. Simulation and Model Development for Auto-Ignition and Reaction Front Propagation in Low-Temperature High-Pressure Lean-Burn Engines. [Doctoral Dissertation]. University of Michigan; 2010. Available from: http://hdl.handle.net/2027.42/78870
5.
Olesky, Laura Katherine.
An Experimental Investigation of the Burn Rates of Naturally Aspirated Spark Assisted Compression Ignition Combustion in a Single Cylinder Engine with Negative Valve Overlap.
Degree: PhD, Mechanical Engineering, 2013, University of Michigan
URL: http://hdl.handle.net/2027.42/99979
► The implementation of homogeneous charge compression ignition (HCCI) in an engine remains a challenge due to the limited operating range and lack of a direct…
(more)
▼ The implementation of homogeneous charge
compression ignition (HCCI) in an engine remains a challenge due to the limited operating range and lack of a direct
ignition timing control mechanism.
Spark assisted compression ignition (SACI) has been shown by several research groups, including the work presented here, to provide such a mechanism, helping to control the phasing and stability of a primarily auto-igniting charge, as well as provide a means of extending the high load limit of HCCI while maintaining high thermal efficiency. The approach used in this study is unique in that flexible engine valve timing allowed for independent control of the thermal/compositional stratification associated with a large internal residual fraction, allowing its effect to be isolated from other thermophysical parameters. In these experiments, a single-cylinder engine equipped with fully-flexible valve actuation was used to explore the effects of
spark assist in controlling peak heat release rates. With
spark assist, a small portion of the heat release occurred via flame propagation, increasing the overall duration of the
combustion event and dramatically reducing peak rates of heat release. At constant engine load and
combustion phasing, peak heat release rates were reduced by 40% by controlling
spark timing and unburned gas temperature via changes in internal and external EGR rates. Internal EGR was adjusted by varying the duration of negative valve overlap (NVO); for the range of NVO investigated, potential variations in in-cylinder mixing and thermal/compositional stratification were found to have a weak effect on burn characteristics, confirming the notion that temperature and
spark timing are the primary variables affecting SACI burn rates for a fixed mixture composition. In the experiments, heat release analysis showed that the behavior of SACI was consistent with the theoretical kinetics associated with turbulent flame propagation and auto-
ignition, supporting the hypothesis that SACI is essentially two distinct energy release events coupled by
compression heating from an expanding flame front. The results of this work provide new insights into the physical and chemical mechanisms important during low temperature
combustion. The results confirm proposed representations of SACI, and thereby provide direction for developing new advanced low temperature engine strategies.
Advisors/Committee Members: Assanis, Dionissios N. (committee member), Wooldridge, Margaret S. (committee member), Driscoll, James F. (committee member), Boehman, Andre L. (committee member), Lavoie, George A. (committee member), Martz, Jason Brian (committee member).
Subjects/Keywords: Spark Assisted Compression Ignition Combustion; Low Temperature Combustion; Mechanical Engineering; Engineering
…laminar flame speed
SA
spark advance
SACI spark assisted compression ignition
SI
spark… …mechanism. Spark assisted compression ignition (SACI) has been shown by
several research… …11], and spark assisted compression ignition [43]. With boosted strategies… …compression ignition (SACI), involves triggering HCCI combustion using a spark-ignited… …ratio
HCCI homogeneous charge compression
ignition
AIT
after (spark) ignition…
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APA ·
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APA (6th Edition):
Olesky, L. K. (2013). An Experimental Investigation of the Burn Rates of Naturally Aspirated Spark Assisted Compression Ignition Combustion in a Single Cylinder Engine with Negative Valve Overlap. (Doctoral Dissertation). University of Michigan. Retrieved from http://hdl.handle.net/2027.42/99979
Chicago Manual of Style (16th Edition):
Olesky, Laura Katherine. “An Experimental Investigation of the Burn Rates of Naturally Aspirated Spark Assisted Compression Ignition Combustion in a Single Cylinder Engine with Negative Valve Overlap.” 2013. Doctoral Dissertation, University of Michigan. Accessed April 13, 2021.
http://hdl.handle.net/2027.42/99979.
MLA Handbook (7th Edition):
Olesky, Laura Katherine. “An Experimental Investigation of the Burn Rates of Naturally Aspirated Spark Assisted Compression Ignition Combustion in a Single Cylinder Engine with Negative Valve Overlap.” 2013. Web. 13 Apr 2021.
Vancouver:
Olesky LK. An Experimental Investigation of the Burn Rates of Naturally Aspirated Spark Assisted Compression Ignition Combustion in a Single Cylinder Engine with Negative Valve Overlap. [Internet] [Doctoral dissertation]. University of Michigan; 2013. [cited 2021 Apr 13].
Available from: http://hdl.handle.net/2027.42/99979.
Council of Science Editors:
Olesky LK. An Experimental Investigation of the Burn Rates of Naturally Aspirated Spark Assisted Compression Ignition Combustion in a Single Cylinder Engine with Negative Valve Overlap. [Doctoral Dissertation]. University of Michigan; 2013. Available from: http://hdl.handle.net/2027.42/99979
6.
Liu, Jinlong.
Investigation of Combustion Characteristics of a Heavy-Duty Diesel Engine Retrofitted to Natural Gas Spark Ignition Operation.
Degree: PhD, Mechanical and Aerospace Engineering, 2018, West Virginia University
URL: https://doi.org/10.33915/etd.3713
;
https://researchrepository.wvu.edu/etd/3713
► The conversion of existing diesel engines to natural-gas spark ignition operation by adding a gas injector in the intake manifold for fuel delivery and…
(more)
▼ The conversion of existing diesel engines to natural-gas
spark ignition operation by adding a gas injector in the intake manifold for fuel delivery and replacing the diesel fuel injector with a
spark plug to initiate and control the
combustion process can reduce U.S. dependence on petroleum imports and curtail engine-out emissions. As the conventional diesel
combustion chamber (i.e., flat head and bowl-in-piston) creates high turbulence, the engine can operate leaner, which would increase its efficiency and reduce emissions. However, natural gas
combustion in such retrofitted engines presents differences compared to that in conventional
spark ignited engines. Subsequently, the main goal of this study was to investigate the characteristics of natural gas
combustion inside a diesel-like, fast-burn
combustion chamber using a unique array of experimental and numerical tools. The experimental platform consisted of a heavy-duty single-cylinder diesel engine converted to natural-gas
spark ignition and operated at a low-speed, lean equivalence ratio, and medium-load condition. The engine can also operate in an optical configuration (i.e., the stock piston and cylinder block can be replaced with a see-through piston and an extended cylinder block), which was used to visualize flame behavior. The optical data indicated a thick and fast-propagated flame in the piston bowl but slower flame propagation inside the squish region. In addition, a 3D numerical model of the optical engine was built to better explain the geometry effects. The simulation results suggested that while the region around the
spark plug location experienced a moderate turbulence that helped with the
ignition process, the interaction of squish, piston motion, and intake swirl created a highly-turbulent environment that favored the fast burn inside the bowl and stabilized the
combustion process. However, the squish region experienced a much lower turbulence, which, combined with the reduced temperature and pressure during the expansion stroke and its higher surface-to-volume ratio, reduced the burning velocity and the flame propagation, but also avoided knocking. Consequently, the bowl-in-piston geometry separated the lean-burn natural gas
combustion into two distinct events. To extend the optical findings, the metal engine configuration was used to investigate the effects of gas composition,
spark timing, equivalence ratio, and engine speed on the two-stage
combustion. The results suggested that operating conditions controlled the magnitude and phasing of the two
combustion events. Moreover, 3D CFD simulations of the metal engine configuration showed that the squish region contained an important mixture fraction that would burn much slower and can increase the phasing separation between the two
combustion events to a point that a second peak would appear in the heat release rate. Moreover, the rapid-burn event in such an engine was much shorter compared to its traditional definition (i.e., the time in crank angle degrees between the 10% and 90%…
Advisors/Committee Members: Cosmin E. Dumitrescu, Nigel N. Clark, Nigel N. Clark.
Subjects/Keywords: Natural gas; Compression ignition engine; Spark ignition operation; Piston shape effects; Bowl-in-piston combustion chamber; Automotive Engineering; Chemical Engineering; Energy Systems; Heat Transfer, Combustion; Mechanical Engineering
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APA ·
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MLA ·
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CSE |
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to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Liu, J. (2018). Investigation of Combustion Characteristics of a Heavy-Duty Diesel Engine Retrofitted to Natural Gas Spark Ignition Operation. (Doctoral Dissertation). West Virginia University. Retrieved from https://doi.org/10.33915/etd.3713 ; https://researchrepository.wvu.edu/etd/3713
Chicago Manual of Style (16th Edition):
Liu, Jinlong. “Investigation of Combustion Characteristics of a Heavy-Duty Diesel Engine Retrofitted to Natural Gas Spark Ignition Operation.” 2018. Doctoral Dissertation, West Virginia University. Accessed April 13, 2021.
https://doi.org/10.33915/etd.3713 ; https://researchrepository.wvu.edu/etd/3713.
MLA Handbook (7th Edition):
Liu, Jinlong. “Investigation of Combustion Characteristics of a Heavy-Duty Diesel Engine Retrofitted to Natural Gas Spark Ignition Operation.” 2018. Web. 13 Apr 2021.
Vancouver:
Liu J. Investigation of Combustion Characteristics of a Heavy-Duty Diesel Engine Retrofitted to Natural Gas Spark Ignition Operation. [Internet] [Doctoral dissertation]. West Virginia University; 2018. [cited 2021 Apr 13].
Available from: https://doi.org/10.33915/etd.3713 ; https://researchrepository.wvu.edu/etd/3713.
Council of Science Editors:
Liu J. Investigation of Combustion Characteristics of a Heavy-Duty Diesel Engine Retrofitted to Natural Gas Spark Ignition Operation. [Doctoral Dissertation]. West Virginia University; 2018. Available from: https://doi.org/10.33915/etd.3713 ; https://researchrepository.wvu.edu/etd/3713
7.
Mouriaux, Sophie.
Simulation aux grandes échelles de l'allumage par bougie turbulent et de la propagation de la flamme dans les Moteurs à allumage commandé : Large Eddy simulation of the turbulent spark ignition and of the flame propagation in spark ignition engines.
Degree: Docteur es, Combustion, 2016, Université Paris-Saclay (ComUE)
URL: http://www.theses.fr/2016SACLC046
► Le fonctionnement en régime très pauvre ou avec forts taux d'EGR des moteurs à allumage commandé (MAC) permet de réduire efficacement les émissions de CO2…
(more)
▼ Le fonctionnement en régime très pauvre ou avec forts taux d'EGR des moteurs à allumage commandé (MAC) permet de réduire efficacement les émissions de CO2 et de Nox ; cependant ces stratégies se heurtent à l'augmentation des variabilités cycliques. Ces dernières sont principalement dues à la phase d'allumage qui devient critique de dilution. Le modèle ECFM-LES actuellement utilisé à IFPEn, basé sur la notion de densité de surface de flamme, est insuffisant pour décrire l'allumage dans ces conditions critiques. Dans ces travaux, l'approche TF-LES est adoptée, l'allumage étant alors décrit par un emballement cinétique des réactions chimiques lors d'une élévations locale de la température. Ces travaux définissent et évaluent une stratégie de simulation pour TF-LES en configuration moteur, qui permette une prédiction fine des allumages critiques et de la propagation turbulente de la flamme, afin de décrire le cycle moteur complet.Dans une première partie, des DNS d'allumages turbulents ont été réalisées, en modélisant la phase d'allumage par un dépôt d'énergie thermique (Lacaze et al., (2009)). Les calculs ont simulé les expériences d'allumage de Cardin et al. (2013), dans lesquelles l'énergie minimum d'allumage (MIE) d'un mélange mtéhane-air a été mesuré, pour différentes richesses pauvres et sous différentes intensités turbulentes. L'objectif principal des simulations a été de déterminer les paramètres numériques et physiques du modèle permettant de reproduire les allumages de l'expérience. Deux types de schémas cinétiques ont été évalués : un schéma simplifié et un schéma analytique (ARC), ce dernier reproduisant et les délais d'auto-allumage et la vitesse de flamme laminaire. Les résultats ont permis de définir des critères d'allumage et de mettre en évidence les différentes prédiction d'allumage avec les deux types de schémas cinétiques. Les résultats ont été également démontré que l'approche choisie permettait de prédire les bons niveaux d'énergie pour les allumages laminaires et à faible nombres de Kalovitz (Ka<10). Aux plus hauts nombres de Karlovitz, il a été montré que le modèle ED était insuffisant pour prédire les énergie d'allumage et qu'une description plus fine du dépôt d'énergie est nécessaire.Dans la seconde partie des travaux, un modèle de plissement dynamique (Wang et al., 2012) a été étudié, afin de décrire le développement hors-équilibre de la flamme dans la phase de propagation turbulente. Des études sur des flammes sphériques laminaires ont d'abord été menées. Ensuite, les premiers tests de configuration moteur ayant révélé des incompatibilités du modèle, des modifications ont été proposées. Le modèle de plissement dynamique modifié a été finalement évalué sur la configuration moteur ICAMDAC. Les résultats obtenus ont été comparés aux résultats obtenus par Robert et al. (2015) avec le modèle ECFM-LES, qui utilise une équation de transport de densité de surface de flamme décrivant le plissement hors-équilibre de la flamme. Les résultats obtenus avec le plissement dynamique sont en très bon accord…
Advisors/Committee Members: Colin, Olivier (thesis director), Veynante, Denis (thesis director).
Subjects/Keywords: Combustion pré-mélangée; Allumage; Moteur à allumage commandé; Premixed combustion; Spark ignition; Spark ignition engines
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APA (6th Edition):
Mouriaux, S. (2016). Simulation aux grandes échelles de l'allumage par bougie turbulent et de la propagation de la flamme dans les Moteurs à allumage commandé : Large Eddy simulation of the turbulent spark ignition and of the flame propagation in spark ignition engines. (Doctoral Dissertation). Université Paris-Saclay (ComUE). Retrieved from http://www.theses.fr/2016SACLC046
Chicago Manual of Style (16th Edition):
Mouriaux, Sophie. “Simulation aux grandes échelles de l'allumage par bougie turbulent et de la propagation de la flamme dans les Moteurs à allumage commandé : Large Eddy simulation of the turbulent spark ignition and of the flame propagation in spark ignition engines.” 2016. Doctoral Dissertation, Université Paris-Saclay (ComUE). Accessed April 13, 2021.
http://www.theses.fr/2016SACLC046.
MLA Handbook (7th Edition):
Mouriaux, Sophie. “Simulation aux grandes échelles de l'allumage par bougie turbulent et de la propagation de la flamme dans les Moteurs à allumage commandé : Large Eddy simulation of the turbulent spark ignition and of the flame propagation in spark ignition engines.” 2016. Web. 13 Apr 2021.
Vancouver:
Mouriaux S. Simulation aux grandes échelles de l'allumage par bougie turbulent et de la propagation de la flamme dans les Moteurs à allumage commandé : Large Eddy simulation of the turbulent spark ignition and of the flame propagation in spark ignition engines. [Internet] [Doctoral dissertation]. Université Paris-Saclay (ComUE); 2016. [cited 2021 Apr 13].
Available from: http://www.theses.fr/2016SACLC046.
Council of Science Editors:
Mouriaux S. Simulation aux grandes échelles de l'allumage par bougie turbulent et de la propagation de la flamme dans les Moteurs à allumage commandé : Large Eddy simulation of the turbulent spark ignition and of the flame propagation in spark ignition engines. [Doctoral Dissertation]. Université Paris-Saclay (ComUE); 2016. Available from: http://www.theses.fr/2016SACLC046
The Ohio State University
8.
Iqbal, Asim.
Fundamentals of Knock.
Degree: PhD, Mechanical Engineering, 2012, The Ohio State University
URL: http://rave.ohiolink.edu/etdc/view?acc_num=osu1338146766
► In view of the declining global oil reserves and the environmental concerns associated with automotive emissions, it is imperative to improve the fuel efficiency of…
(more)
▼ In view of the declining global oil reserves and the
environmental concerns associated with automotive emissions, it is
imperative to improve the fuel efficiency of engines. Using higher
compression ratios or boosting the specific output through
turbocharging are proven strategies to accomplish this goal.
However, the ability to achieve elevated peak pressures required by
either mechanism to be effective is limited by knock. The lack of
understanding of knock also hinders the realization of potential
benefits of homogeneous charge
compression ignition, a promising
technology that relies on controlled autoignition. Thus, knock is
one of the most serious obstacles in the development of fuel
efficient engines. For this reason, the phenomenon of knock has
been studied extensively, but even after more than a century of
mostly experimental research, the basic mechanism governing knock
remains poorly understood. In order to develop a fundamental
understanding of engine knock, detailed chemical kinetic modeling
of the hydrocarbon oxidation mechanism associated with the
autoignition process is conducted in CHEMKIN (a chemical kinetics
software). Based on the insight gained from kinetic modeling, some
of the key reactions and species that are instrumental to the
autoignition of hydrocarbons are identified. The sensitivity of
knock to various parameters including inlet pressure, inlet
temperature,
compression ratio, wall temperature, fuel-air
equivalence ratio, and exhaust gas recirculation (EGR) is examined
through CHEMKIN simulations.
Ignition delay predictions for the
autoignition of a toluene reference fuel (TRF) blend with an
antiknock index of 91 (TRF 91), obtained through extensive chemical
kinetic modeling in CHEMKIN for a constant volume reactor, are used
to develop an improved
ignition delay correlation for predicting
knock in
spark ignition (SI) engines. In addition to NOx control,
EGR is increasingly being utilized for managing
combustion phasing
in SI engines to mitigate knock. Therefore, along with other
operating parameters, the effects of EGR on autoignition are
incorporated into the correlation to address the need for
predicting
ignition delay in SI engines operating with EGR. The
modeling approach adopted for TRF 91 is then extended to develop an
ignition delay correlation for an oxygenated surrogate fuel blend
of 87 octane gasoline (with 10% ethanol). In addition, a
conceptually new approach based on multiple timescales is developed
to predict
ignition delay for the autoignition of a primary
reference fuel blend. Finally, the new
ignition delay correlation
for TRF 91 is implemented into the engine simulation tool GT-POWER
and engine dynamometer experiments with knocking
combustion are
conducted to validate the knock predictions from the correlation.
Comparison of knock onset predictions from GT-POWER with engine
experiments illustrates the accuracy of the TRF 91
ignition delay
correlation. Hence, the contributions of the present study include
an enhanced understanding of the underlying physics governing…
Advisors/Committee Members: Selamet, Ahmet (Advisor).
Subjects/Keywords: Mechanical Engineering; Knock; Spark Ignition Engines; Combustion; Ignition Delay; Kinetics; Ignition Delay Correlation
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Manager
APA (6th Edition):
Iqbal, A. (2012). Fundamentals of Knock. (Doctoral Dissertation). The Ohio State University. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=osu1338146766
Chicago Manual of Style (16th Edition):
Iqbal, Asim. “Fundamentals of Knock.” 2012. Doctoral Dissertation, The Ohio State University. Accessed April 13, 2021.
http://rave.ohiolink.edu/etdc/view?acc_num=osu1338146766.
MLA Handbook (7th Edition):
Iqbal, Asim. “Fundamentals of Knock.” 2012. Web. 13 Apr 2021.
Vancouver:
Iqbal A. Fundamentals of Knock. [Internet] [Doctoral dissertation]. The Ohio State University; 2012. [cited 2021 Apr 13].
Available from: http://rave.ohiolink.edu/etdc/view?acc_num=osu1338146766.
Council of Science Editors:
Iqbal A. Fundamentals of Knock. [Doctoral Dissertation]. The Ohio State University; 2012. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=osu1338146766
Mississippi State University
9.
Polk, Andrew C.
Detailed characterization of conventional and low temperature dual fuel combustion in compression ignition engines.
Degree: PhD, Mechanical Engineering, 2013, Mississippi State University
URL: http://sun.library.msstate.edu/ETD-db/theses/available/etd-04012013-092845/
;
► The goal of this study is to assess conventional and low temperature dual fuel combustion in light- and heavy-duty multi-cylinder compression ignition engines in…
(more)
▼ The goal of this study is to assess conventional and low temperature dual fuel
combustion in light- and heavy-duty multi-cylinder
compression ignition engines in terms of
combustion characterization, performance, and emissions. First, a light-duty
compression ignition engine is converted to a dual fuel engine and instrumented for in-cylinder pressure measurements. The primary fuels, methane and propane, are each introduced into the system by means of fumigation before the turbocharger, ensuring the air-fuel composition is well-mixed. Experiments are performed at 2.5, 5, 7.5, and 10 bar BMEP at an engine speed of 1800 RPM. Heat release analyses reveal that the
ignition delay and subsequent
combustion processes are dependent on the primary fuel type and concentration, pilot quantity, and loading condition. At low load, diesel-ignited propane yields longer
ignition delay periods than diesel-ignited methane, while at high load the reactivity of propane is more pronounced, leading to shorter
ignition delays. At high load (BMEP = 10 bar), the rapid heat release associated with diesel-ignited propane appears to occur even before pilot injection, possibly indicating auto-
ignition of the propane-air mixture. Next, a modern, heavy-duty
compression ignition engine is commissioned with an open architecture controller and instrumented for in-cylinder pressure measurements. Initial diesel-ignited propane dual fuel experiments (fumigated before the turbocharger) at 1500 RPM reveal that the maximum percent energy substitution (PES) of propane is limited to 86, 60, 33, and 25 percent at 5, 10, 15, and 20 bar BMEP, respectively. Fueling strategy, injection strategy, exhaust gas recirculation (EGR) rate, and intake boost pressure are varied in order to maximize the PES of propane at 10 bar BMEP, which increases from 60 PES to 80 PES of propane. Finally, diesel-ignited propane dual fuel low temperature
combustion (LTC) is implemented using early injection timings (50 DBTDC) at 5 bar BMEP. A sweep of injection timings from 10 DBTDC to 50 DBTDC reveals the transition from conventional to low temperature dual fuel
combustion, indicated by ultra-low NO
x and smoke emissions. Optimization of the dual fuel LTC concept yields less than 0.02 g/kW-hr NO
x and 0.06 FSN smoke at 93 PES of propane.
Advisors/Committee Members: Sundar R. Krishnan (chair), Kalyan K. Srinivasan (chair), Rogelio Luck (committee member), D. Keith Walters (committee member).
Subjects/Keywords: compression ignition; propane; combustion; dual fuel; LTC
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APA ·
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CSE |
Export
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Manager
APA (6th Edition):
Polk, A. C. (2013). Detailed characterization of conventional and low temperature dual fuel combustion in compression ignition engines. (Doctoral Dissertation). Mississippi State University. Retrieved from http://sun.library.msstate.edu/ETD-db/theses/available/etd-04012013-092845/ ;
Chicago Manual of Style (16th Edition):
Polk, Andrew C. “Detailed characterization of conventional and low temperature dual fuel combustion in compression ignition engines.” 2013. Doctoral Dissertation, Mississippi State University. Accessed April 13, 2021.
http://sun.library.msstate.edu/ETD-db/theses/available/etd-04012013-092845/ ;.
MLA Handbook (7th Edition):
Polk, Andrew C. “Detailed characterization of conventional and low temperature dual fuel combustion in compression ignition engines.” 2013. Web. 13 Apr 2021.
Vancouver:
Polk AC. Detailed characterization of conventional and low temperature dual fuel combustion in compression ignition engines. [Internet] [Doctoral dissertation]. Mississippi State University; 2013. [cited 2021 Apr 13].
Available from: http://sun.library.msstate.edu/ETD-db/theses/available/etd-04012013-092845/ ;.
Council of Science Editors:
Polk AC. Detailed characterization of conventional and low temperature dual fuel combustion in compression ignition engines. [Doctoral Dissertation]. Mississippi State University; 2013. Available from: http://sun.library.msstate.edu/ETD-db/theses/available/etd-04012013-092845/ ;
Universitat Politècnica de València
10.
Valero Marco, Jorge.
Analysis of the potential of SI lean combustion and CAI combustion in a two-stroke spark-assisted gasoline engine
.
Degree: 2020, Universitat Politècnica de València
URL: http://hdl.handle.net/10251/138556
► [EN] Internal combustion engines are in a situation in which they must be cleaner and more efficient than they have ever been. This change is…
(more)
▼ [EN] Internal
combustion engines are in a situation in which they must be cleaner and more efficient than they have ever been. This change is motivated by the global and continuous evolution of the emissions regulations linked to their commercialization, which try to establish the path to protect the human health, and move towards more sustainable energetic models.
Framed in this context, the research work developed in this PhD thesis has focused on the way to continue improving the
spark ignition engines. To this end, a prototype two-stroke engine has been used, with the idea of studying the
Spark Ignited
combustion in lean conditions ('lean SI') and the Controlled Auto-
Ignition combustion 'CAI'). In this way, the traditional 'SI' operation in stoichiometric conditions of this type of engines is replaced, looking for an improvement in fuel efficiency, and a reduction, at the same time, of the pollutant emissions.
This work has been approached mainly from an experimental point of view. Firstly, different works have been performed on the engine: operation of the different
combustion modes, definition of the operating strategies, and compilation of experimental data coming from the engine operation in the different regions of the engine map. And, secondly, all this data has been analyzed and studied in detail to define the strengths and weaknesses of each
combustion mode applied to the different engine operating conditions.
The combination of these two works has led to obtain a large amount of data about the achievable efficiencies and the emissions values obtained in each
combustion mode. And, in addition, the influence on the
combustion of the burned gases recirculation in the engine ('EGR'), has also been studied as a strategy to reduce emissions, and control the
combustion at high loads in both
combustion modes.
Regarding the analytical part of the work, several problems have been detected. Firstly, the high
combustion variability in this engine, and secondly, the coupling of two completely different
combustion modes. These issues have generated the need to analyze the data obtained in a more detailed way, in order to get more information about the
combustion process. To solve these two aspects, first, a different point of view has been raised when dealing with the
combustion diagnosis, the cycle to cycle analysis, and secondly, a
combustion analysis methodology has been proposed in order to allow the
combustion analysis from a more detailed point of view. In this way the
combustion development is studied, and thus, the differentiation between the different
combustion events that take place in the engine can be studied.
All this work has been useful to define the strategies to operate the whole engine map by combining the 'lean SI' and 'CAI'
combustion modes. This solution, compared to the current Euro VI engines, has presented higher efficiency values complying with the established emissions limits, showing in this way, the high potential of these
combustion modes applied to 'SI' engines, as well as a real…
Advisors/Committee Members: López Sánchez, José Javier (advisor).
Subjects/Keywords: Two-stoke engine; engines developement; CAI (Controlled Auto-Ignition); SI (Spark Ignition); Lean Combustion; advanced combustion modes; combustion analysis; instantaneous cycles; cycle to cycle variation; air-assisted injection; HRL (Heat Release Law); combustion speed.
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APA ·
Chicago ·
MLA ·
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CSE |
Export
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Manager
APA (6th Edition):
Valero Marco, J. (2020). Analysis of the potential of SI lean combustion and CAI combustion in a two-stroke spark-assisted gasoline engine
. (Doctoral Dissertation). Universitat Politècnica de València. Retrieved from http://hdl.handle.net/10251/138556
Chicago Manual of Style (16th Edition):
Valero Marco, Jorge. “Analysis of the potential of SI lean combustion and CAI combustion in a two-stroke spark-assisted gasoline engine
.” 2020. Doctoral Dissertation, Universitat Politècnica de València. Accessed April 13, 2021.
http://hdl.handle.net/10251/138556.
MLA Handbook (7th Edition):
Valero Marco, Jorge. “Analysis of the potential of SI lean combustion and CAI combustion in a two-stroke spark-assisted gasoline engine
.” 2020. Web. 13 Apr 2021.
Vancouver:
Valero Marco J. Analysis of the potential of SI lean combustion and CAI combustion in a two-stroke spark-assisted gasoline engine
. [Internet] [Doctoral dissertation]. Universitat Politècnica de València; 2020. [cited 2021 Apr 13].
Available from: http://hdl.handle.net/10251/138556.
Council of Science Editors:
Valero Marco J. Analysis of the potential of SI lean combustion and CAI combustion in a two-stroke spark-assisted gasoline engine
. [Doctoral Dissertation]. Universitat Politècnica de València; 2020. Available from: http://hdl.handle.net/10251/138556
Universitat Politècnica de València
11.
Pagano, Vincenzo.
Analysis of a stratified pre-chamber spark ignition system under lean mixture conditions
.
Degree: 2020, Universitat Politècnica de València
URL: http://hdl.handle.net/10251/152486
► [EN] In the current work, the characterization of the combustion process inside a stratified pre-chamber spark ignition (PCSI) system is performed. An extensive bibliographical review…
(more)
▼ [EN] In the current work, the characterization of the
combustion process inside a stratified pre-chamber
spark ignition (PCSI) system is performed. An extensive bibliographical review about the pre-chamber systems developed from the second half of the 20th century until modern times is presented. The review shows that the latest generation systems have the potential to accomplish the emissions limits while providing high performance and low fuel consumption. Nevertheless, many efforts of the scientific community are still needed to allow the large-scale application of the technology. Indeed, based on the outstanding challenges observed, the investigation plan is developed including both experimental and numerical parts. All experiments were performed by means of the rapid compressionexpansion machine (RCEM) in the CMT-Motores Térmicos laboratory. The original cylinder head layout was modified to allow the housing of the prechamber itself, fuel injectors,
spark plug, pressure transducers in both chamber, and a thermocouple. The test methodology involved the acquisition of the pressure evolution in both main chamber and pre-chamber, the piston position (used to compute the instantaneous cylinder volume), the duration of the auxiliary injection, and the
spark ignition point. These are used as input for the zero-dimensional thermodynamic model which simulates the fundamental parameters aims to characterize the PCSI system working cycle. Therefore, a deeper knowledge of the mass interchanged process, induced turbulence field, heat release rate,
combustion speed, and flame regime is generated. Subsequently, to calibrate the zero-dimensional model coefficients under motoring conditions, several 3D CFD simulations were carried out by means of Converge software. Hence, the results of the simulations in terms of interchanged mass and pre-chamber turbulent kinetic energy have been used to calibrate the nozzle discharge coefficient and the turbulence sub-model coefficients for all the pre-chamber geometries. Furthermore, the 3D CFD simulations outputs are analysed to fully understand the flow field structure and the local effect induced by the different nozzles at the
spark activation time. The turbulent kinetic energy in terms of intensity and orientation is investigated over several relevant pre-chamber sections. The results reveal a clear relationship between the turbulence developed within the pre-chamber and the orifices structure. Straight orifices or perpendicular jets impact, promote more intense local turbulence due to direct collision while tilted orifices guarantee more homogeneity due to the swirling motion. Additionally, increase the orifice numbers shows benefits on the fluid dynamic homogeneity. Thus, preceding the experimental campaign several fundamental aspects of the system are evaluated. The cycle-to-cycle dispersion is explored by means of the statistical assessment showing low pressure peak deviation. The auxiliary injection pressure and timing are optimized for avoiding wall wetting phenomena while…
Advisors/Committee Members: Morena Borja, Joaquín de la (advisor).
Subjects/Keywords: Pre-chamber Spark Ignition System;
Torch Jet Ignition;
Flame Propagation;
Nozzle Geometry;
Combustion Speed;
Heat Release Rate;
Stratified System;
Natural Chemiluminescence;
Combustion Visualization;
Rapid Compression-Expansion Machine;
Combustion Efficiency;
Turbulent Kinetic Energy;
CFD Simulations;
0D Thermodynamic Model
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Record Details
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Pagano, V. (2020). Analysis of a stratified pre-chamber spark ignition system under lean mixture conditions
. (Doctoral Dissertation). Universitat Politècnica de València. Retrieved from http://hdl.handle.net/10251/152486
Chicago Manual of Style (16th Edition):
Pagano, Vincenzo. “Analysis of a stratified pre-chamber spark ignition system under lean mixture conditions
.” 2020. Doctoral Dissertation, Universitat Politècnica de València. Accessed April 13, 2021.
http://hdl.handle.net/10251/152486.
MLA Handbook (7th Edition):
Pagano, Vincenzo. “Analysis of a stratified pre-chamber spark ignition system under lean mixture conditions
.” 2020. Web. 13 Apr 2021.
Vancouver:
Pagano V. Analysis of a stratified pre-chamber spark ignition system under lean mixture conditions
. [Internet] [Doctoral dissertation]. Universitat Politècnica de València; 2020. [cited 2021 Apr 13].
Available from: http://hdl.handle.net/10251/152486.
Council of Science Editors:
Pagano V. Analysis of a stratified pre-chamber spark ignition system under lean mixture conditions
. [Doctoral Dissertation]. Universitat Politècnica de València; 2020. Available from: http://hdl.handle.net/10251/152486
Indian Institute of Science
12.
Pandey, Sunil Kumar.
Exploration And Assessment of HCCI Strategies for a Multi-Cylinder Heavy-Duty Diesel Engine.
Degree: PhD, Faculty of Engineering, 2017, Indian Institute of Science
URL: http://etd.iisc.ac.in/handle/2005/2720
► Homogeneous Charge Compression Ignition (HCCI) combustion is an alternative combustion mode in which the fuel is homogeneously mixed with air and is auto-ignited by compression.…
(more)
▼ Homogeneous Charge
Compression Ignition (HCCI)
combustion is an alternative
combustion mode in which the fuel is homogeneously mixed with air and is auto-ignited by
compression. Due to charge homogeneity, this mode is characterized by low equivalence ratios and temperatures giving simultaneously low nitric oxide (NOx) and soot in diesel engines. The conventional problem of NOx-soot trade-off is avoided in this mode due to absence of diffusion
combustion. This mode can be employed at part load conditions while maintaining conventional
combustion at high load thus minimizing regulatory cycle emissions and reducing cost of after-treatment systems. The present study focuses on achieving this mode in a turbocharged, common rail, direct injection, four-cylinder, heavy duty diesel engine. Specifically, the work involves a combination of three-dimensional CFD simulations and experiments on this engine to assess both traditional and novel strategies related to fuel injection.
The first phase of the work involved a quasi-dimensional simulation of the engine to assess potential of achieving HCCI. This was done using a zero-dimensional, single-zone HCCI
combustion model with n-heptane skeletal chemistry along with a one-dimensional model of intake and exhaust systems. The feasibility of operation with realistic knock values with high EGR rate of 60% was observed. The second aspect of the work involved three-dimensional CFD simulations of the in-cylinder process with wall film prediction to evaluate injection strategies associated with Early Direct Injection (EDI). The extended Coherent Flame Model-3Zone (ECFM-3Z) was employed for
combustion simulation of conventional CI and EDI, and was validated with experimental in-cylinder pressure data from the engine. A new Uniformity Index (UI) parameter was defined to assess charge homogeneity. Results showed significant in-homogeneity and presence of wall film for EDI. Simulations were conducted to assess improvement of charge homogeneity by several strategies; narrow spray cone angle, injection timing, multiple injections, intake air heating, Port Fuel Injection (PFI) as well as combination of PFI and EDI. The maximum UI achieved by EDI was 0.78. The PFI strategy could achieve UI of 0.95; however, up to 50% of fuel remained trapped in the port after valve closure. This indicated that except EDI, none of the above-mentioned strategies could help achieve the benefits of the HCCI mode.
The third part of the work involved engine experimentation to assess the EDI strategy. This strategy produced lower soot than that of conventional CI
combustion with very short
combustion duration, but led to high knock and NOx which is attributed to pool fire burning phenomenon of the wall film, as confirmed by CFD. An Optimized EDI (OptimEDI) strategy was then developed based on results of CFD and Design of Experiments. The Optim EDI consisted of triple injections with split ratio of 41%-45%-14% and advancing the first injection. This strategy gave 20% NOx and soot reduction over the conventional CI…
Advisors/Committee Members: Ravikrishna, R V (advisor).
Subjects/Keywords: Homogeneous Charge Compression Ignition Engines (HCCI); Low Temperature Combustion; Multi-Cylinder Heavy-Duty Diesel Engines; Diesel Motor; Diesel Engines; Early Direct Injection; Air-Assisted Injection; Combustion; Diesel Homogeneous Charge Compression Ignition; Diesel Fuels; Diesel-Fueled Engines; Fuel Injection; Internal Combustion Engines; Computational Fluid Dynamics; Mechanical Engineering
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Pandey, S. K. (2017). Exploration And Assessment of HCCI Strategies for a Multi-Cylinder Heavy-Duty Diesel Engine. (Doctoral Dissertation). Indian Institute of Science. Retrieved from http://etd.iisc.ac.in/handle/2005/2720
Chicago Manual of Style (16th Edition):
Pandey, Sunil Kumar. “Exploration And Assessment of HCCI Strategies for a Multi-Cylinder Heavy-Duty Diesel Engine.” 2017. Doctoral Dissertation, Indian Institute of Science. Accessed April 13, 2021.
http://etd.iisc.ac.in/handle/2005/2720.
MLA Handbook (7th Edition):
Pandey, Sunil Kumar. “Exploration And Assessment of HCCI Strategies for a Multi-Cylinder Heavy-Duty Diesel Engine.” 2017. Web. 13 Apr 2021.
Vancouver:
Pandey SK. Exploration And Assessment of HCCI Strategies for a Multi-Cylinder Heavy-Duty Diesel Engine. [Internet] [Doctoral dissertation]. Indian Institute of Science; 2017. [cited 2021 Apr 13].
Available from: http://etd.iisc.ac.in/handle/2005/2720.
Council of Science Editors:
Pandey SK. Exploration And Assessment of HCCI Strategies for a Multi-Cylinder Heavy-Duty Diesel Engine. [Doctoral Dissertation]. Indian Institute of Science; 2017. Available from: http://etd.iisc.ac.in/handle/2005/2720
Michigan State University
13.
Zhang, Shupeng.
Modeling and mode transition control of an HCCI capable Si engine.
Degree: 2014, Michigan State University
URL: http://etd.lib.msu.edu/islandora/object/etd:2492
► Thesis Ph. D. Michigan State University. Mechanical Engineering 2014.
While the homogeneous charge compression ignition (HCCI) combustion has its advantages of high thermal efficiency with…
(more)
▼ Thesis Ph. D. Michigan State University. Mechanical Engineering 2014.
While the homogeneous charge compression ignition (HCCI) combustion has its advantages of high thermal efficiency with low emissions, its operational range is limited in both engine speed and load. To utilize the advantage of the HCCI combustion an HCCI capable SI (spark ignition) engine is required. One of the key challenges of developing such an engine is to achieve smooth mode transition between SI and HCCI combustion, where the in-cylinder thermal and charge mixture properties are quite different due to the distinct combustion characteristics. In this research, mode transition between SI and HCCI combustion was investigated for an HCCI capable SI engine equipped with electrical variable valve timing (EVVT) systems, dual-lift valves and electronic throttle control (ETC) system. For the purpose of reducing research cost and development duration, one of the most efficient approaches is to develop and validate the control strategy using an HIL (hardware-in-the-loop) simulation environment, where the real engine is replaced by a control-oriented real-time engine model. This dissertation describes a two-zone HCCI combustion model, where the in-cylinder charge is divided into the well-mixed and unmixed zones as the result of charge mixing. Simplified fluid dynamics is used to predict the residual gas fraction before the combustion phase starts, which defines the mass of the unmixed zone, during real-time simulations. The unmixed zone size not only determines how well the in-cylinder charge is mixed, which affects the start of HCCI combustion, but also the resulting peak in-cylinder pressure and temperature during the combustion process. The developed model was validated in the HIL simulation and experiments.To achieve smooth combustion mode transition, the throttle position needs to be controlled accurately with fast response. In this dissertation, an electronic throttle control (ETC) system was modeled as an LPV (linear parameter varying) system in discrete-time domain, where the nonlinearities are modeled as varying parameter or compensated through feed-forward control. Mixed constrained H2/Hinf LPV controller was designed to achieve the best performance and also guarantee the system robustness. Then a model-based mode transition control strategy between SI and HCCI combustion was developed and experimentally validated for an HCCI capable SI engine equipped with electrical variable valve timing (EVVT) systems, dual-lift valves and ETC system. During the mode transition, a manifold air pressure controller was used to track the desired intake manifold pressure for managing the charge air; and an iterative learning fuel mass controller, combined with sensitivity-based compensation, was used to manage the engine torque in terms of net effective mean pressure, an indicator of engine output torque, at the desired level for smooth mode transition. Experiment results show that the developed controller is able to achieve smooth combustion mode transition…
Advisors/Committee Members: Zhu, Guoming, Khalil, Hassan, Schock, Harold, Choi, Jongeun.
Subjects/Keywords: Mechanical engineering; Internal combustion engines – Combustion; Spark ignition engines – Combustion; Hardware-in-the-loop simulation
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APA (6th Edition):
Zhang, S. (2014). Modeling and mode transition control of an HCCI capable Si engine. (Thesis). Michigan State University. Retrieved from http://etd.lib.msu.edu/islandora/object/etd:2492
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Zhang, Shupeng. “Modeling and mode transition control of an HCCI capable Si engine.” 2014. Thesis, Michigan State University. Accessed April 13, 2021.
http://etd.lib.msu.edu/islandora/object/etd:2492.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Zhang, Shupeng. “Modeling and mode transition control of an HCCI capable Si engine.” 2014. Web. 13 Apr 2021.
Vancouver:
Zhang S. Modeling and mode transition control of an HCCI capable Si engine. [Internet] [Thesis]. Michigan State University; 2014. [cited 2021 Apr 13].
Available from: http://etd.lib.msu.edu/islandora/object/etd:2492.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Zhang S. Modeling and mode transition control of an HCCI capable Si engine. [Thesis]. Michigan State University; 2014. Available from: http://etd.lib.msu.edu/islandora/object/etd:2492
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Colorado
14.
Cameron, Drew Morales.
Autoignition Studies of Gasoline Surrogate Fuels in the Advanced Fuel Ignition Delay Analyzer.
Degree: MS, Mechanical Engineering, 2017, University of Colorado
URL: https://scholar.colorado.edu/mcen_gradetds/150
► Improving vehicle efficiency is a substantial way to reduce CO2 emissions from the transportation sector. The most limiting factor of spark ignition (SI) gasoline engine…
(more)
▼ Improving vehicle efficiency is a substantial way to reduce CO
2 emissions from the transportation sector. The most limiting factor of
spark ignition (SI) gasoline engine efficiency is the phenomenon known as knocking. The current methods to characterize fuel knock resistance are with the Research Octane Number (RON) and Motor Octane Number (MON) methods. However, it has been shown that these engine-based test methods do not directly predict knock resistance in modern direct injection (DI) gasoline engines, especially under boosted conditions. Alternative test devices have been used to more directly study
ignition kinetics. Constant volume
combustion chambers (CVCCs) have been used to obtain valuable autoignition data at a broader ranger of pressure and temperature conditions than the single point engine operating conditions of the RON and MON tests. This study uses a new CVCC to study gasoline range fuels at engine relevant conditions to collect autoignition data on a set of simple gasoline surrogate fuels and correlate these data to the fuel chemistry and properties. A set of nine gasoline surrogates, with and without oxygenates were tested in the Advanced Fuel
Ignition Delay Analyzer (AFIDA). The main outputs of this study are 3D surfaces of autoignition (
ignition delay time) as a function of pressure and temperature. These data more completely characterize
ignition delay at a wide range of engine relevant conditions, providing more insight than the RON and MON tests. Linear regression was performed between the
ignition delay time and the fuel composition and properties, however significant correlations were not found. This study paves the way for more complex, full-boiling range gasoline fuels to be characterized in the AFIDA, fuels which are too complex to model with chemical kinetics.
Advisors/Committee Members: John W. Daily, Peter Hamlington, Nicole Labbe.
Subjects/Keywords: auto-ignition; combustion; fuel; gasoline surrogate; ignition kinetics; spark ignition engine; Advanced Fuel Ignition Delay Analyzer (AFIDA); Chemistry; Mechanical Engineering
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APA (6th Edition):
Cameron, D. M. (2017). Autoignition Studies of Gasoline Surrogate Fuels in the Advanced Fuel Ignition Delay Analyzer. (Masters Thesis). University of Colorado. Retrieved from https://scholar.colorado.edu/mcen_gradetds/150
Chicago Manual of Style (16th Edition):
Cameron, Drew Morales. “Autoignition Studies of Gasoline Surrogate Fuels in the Advanced Fuel Ignition Delay Analyzer.” 2017. Masters Thesis, University of Colorado. Accessed April 13, 2021.
https://scholar.colorado.edu/mcen_gradetds/150.
MLA Handbook (7th Edition):
Cameron, Drew Morales. “Autoignition Studies of Gasoline Surrogate Fuels in the Advanced Fuel Ignition Delay Analyzer.” 2017. Web. 13 Apr 2021.
Vancouver:
Cameron DM. Autoignition Studies of Gasoline Surrogate Fuels in the Advanced Fuel Ignition Delay Analyzer. [Internet] [Masters thesis]. University of Colorado; 2017. [cited 2021 Apr 13].
Available from: https://scholar.colorado.edu/mcen_gradetds/150.
Council of Science Editors:
Cameron DM. Autoignition Studies of Gasoline Surrogate Fuels in the Advanced Fuel Ignition Delay Analyzer. [Masters Thesis]. University of Colorado; 2017. Available from: https://scholar.colorado.edu/mcen_gradetds/150
Michigan Technological University
15.
Chen, Wei.
Impact of Spark Ignition Duration, Energy and Phasing on Combustion and Performance in a Gasoline Turbocharged Direct Injection Engine near the Dilute Limit.
Degree: PhD, Department of Mechanical Engineering-Engineering Mechanics, 2015, Michigan Technological University
URL: https://digitalcommons.mtu.edu/etdr/11
► High dilution combustion is a promising technology to continue improving gasoline spark-ignition (SI) engine fuel conversion efficiency and for the reduction of nitrogen oxide…
(more)
▼ High dilution
combustion is a promising technology to continue improving gasoline
spark-
ignition (SI) engine fuel conversion efficiency and for the reduction of nitrogen oxide emissions. Dilution is principally limited in SI engines by
ignition, flame kernel development, successful transition to the turbulent propagating flame during the bulk burn portion of
combustion process and the resulting
combustion stability. However, the SI gasoline turbocharged directed injection (GTDI) engine
ignition requirements, especially at the
combustion stability limit, are not well understood and must be better characterized to enable improved designs.
A multi-discharge, electronically control, inductive
ignition system was employed on a multi-cylinder GTDI engine to control and quantify the
ignition and
combustion processes under high dilution operation. The
ignition system, developed by Ford Motor Company and integrated on the engine, is a Variable Output
Ignition System (VOIS) enabling flexible
spark discharge patterns with control of
ignition energy, duration, and phasing. In this study two coil discharges were examined under both continuous and discontinuous settings by delaying the second discharge with respect to the first.
Ignition secondary voltage and current were measured with a high speed analog to digital recorder to measure and quantify the breakdown voltages,
ignition duration,
ignition energy, and other
ignition metrics over 300 cycles of continuous engine operation. Simultaneously 300 cycles of crank-angle resolved cylinder pressure and other data was recorded to analyze cycle based work and
combustion rates and to correlate
ignition with
combustion.
With respect to
ignition analysis and correlations, the results show that the breakdown voltage of the second discharge was correlated to the second coil discharge timing. The second breakdown voltage increased when the second coil discharge timing was retarded. It was also found that the glow energy was highly correlated to the
ignition duration on a cycle-by-cycle basis. The
ignition duration decreases with higher
ignition voltages during glow discharge giving higher total glow energy as a result of hypothesized arc stretching.
With respect to
ignition and
combustion correlations, the flame kernel development period was found to be weakly correlated to both the
ignition duration and energy. The breakdown and arc energy of the second discharge had higher correlation to the
combustion phasing than the glow energy of the second discharge.
With respect to engine performance in a dual-coil multi-discharge
ignition, an optimal
ignition energy phase delay time exists with a fixed total
ignition energy. A delayed second coil discharge at the dilution limit can convert abnormal
combustion cycles to normal burn cycles. The
combustion phasing of these converted cycles is dependent on the phasing of the second discharge. The results also showed that
combustion phasing was strongly correlated to the flame kernel development period. The gross…
Advisors/Committee Members: Jeffery D. Naber, Bo Chen.
Subjects/Keywords: Dual-coil Ignition System; EGR Limit; Direct Injection Spark Ignition Engine; Combustion Stability; Ignition Energy; Ignition Duration; Automotive Engineering
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APA ·
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Manager
APA (6th Edition):
Chen, W. (2015). Impact of Spark Ignition Duration, Energy and Phasing on Combustion and Performance in a Gasoline Turbocharged Direct Injection Engine near the Dilute Limit. (Doctoral Dissertation). Michigan Technological University. Retrieved from https://digitalcommons.mtu.edu/etdr/11
Chicago Manual of Style (16th Edition):
Chen, Wei. “Impact of Spark Ignition Duration, Energy and Phasing on Combustion and Performance in a Gasoline Turbocharged Direct Injection Engine near the Dilute Limit.” 2015. Doctoral Dissertation, Michigan Technological University. Accessed April 13, 2021.
https://digitalcommons.mtu.edu/etdr/11.
MLA Handbook (7th Edition):
Chen, Wei. “Impact of Spark Ignition Duration, Energy and Phasing on Combustion and Performance in a Gasoline Turbocharged Direct Injection Engine near the Dilute Limit.” 2015. Web. 13 Apr 2021.
Vancouver:
Chen W. Impact of Spark Ignition Duration, Energy and Phasing on Combustion and Performance in a Gasoline Turbocharged Direct Injection Engine near the Dilute Limit. [Internet] [Doctoral dissertation]. Michigan Technological University; 2015. [cited 2021 Apr 13].
Available from: https://digitalcommons.mtu.edu/etdr/11.
Council of Science Editors:
Chen W. Impact of Spark Ignition Duration, Energy and Phasing on Combustion and Performance in a Gasoline Turbocharged Direct Injection Engine near the Dilute Limit. [Doctoral Dissertation]. Michigan Technological University; 2015. Available from: https://digitalcommons.mtu.edu/etdr/11
16.
Ahmed, Irufan.
Simulation of turbulent flames relevant to spark-ignition engines.
Degree: PhD, 2014, University of Cambridge
URL: https://www.repository.cam.ac.uk/handle/1810/245288https://www.repository.cam.ac.uk/bitstream/1810/245288/2/license.txt
;
https://www.repository.cam.ac.uk/bitstream/1810/245288/3/license_rdf
;
https://www.repository.cam.ac.uk/bitstream/1810/245288/4/thesis_ahmed.pdf.txt
;
https://www.repository.cam.ac.uk/bitstream/1810/245288/5/thesis_ahmed.pdf.jpg
► Combustion research currently aims to reduce emissions, whilst improving the fuel economy. Burning fuel in excess of air, or lean-burn combustion, is a promising alternative…
(more)
▼ Combustion research currently aims to reduce emissions, whilst improving the fuel economy. Burning fuel in excess of air, or lean-burn combustion, is a promising alternative to conventional combustion, and can achieve these requirements simultaneously. However, lean-burn combustion poses new challenges, especially for internal combustion (IC) engines. Therefore, models used to predict such combustion have to be reliable, accurate and robust.
In this work, the flamelet approach in the Reynolds-Averaged Navier- Stokes framework, is used to simulate flames relevant to spark-ignition IC engines. A central quantity in the current modelling approach is the scalar dissipation rate, which represents coupling between reaction and diffusion, as well as the flame front dynamics.
In the first part of this thesis, the predictive ability of two reaction rate closures, viz. strained and unstrained flamelet models, are assessed through a series of experimental test cases. These cases are: spherically propagating methane- and hydrogen-air flames and combustion in a closed vessel. In addition to these models, simpler algebraic closures are also used for comparison.
It is shown that the strained flamelet model can predict unconfined, spherically propagating methane-air flames reasonably well. By comparing spherical flame results with planar flames, under identical thermochemical and turbulence conditions, it is shown that the turbulent flame speed of spherical flames are 10 to 20% higher than that of planar flames, whilst the mean reaction rates are less influenced by the flame geometry.
Growth of the flame brush thickness in unsteady spherical flames have been attributed to turbulent diffusion in past studies. However, the present analyses revealed that the dominant cause for this increase is the heat-release induced convective effects, which is a novel observation.
Unlike methane-air flames, hydrogen-air flames have non-unity Lewis numbers. Hence, a novel two degrees of freedom approach, using two progress variables, is used to describe the thermochemistry of hydrogen-air flames. Again, it is shown that the strained flamelet model is able to predict the experimental flame growth for stoichiometric hydrogen-air flames. However, none of the models used in this work were able to predict lean hydrogen-air flames. This is because these flames are thermo-diffusively unstable and the current approach is inadequate to represent them.
When combustion takes place inside a closed vessel, the compression of the end gases by the propagating flame causes the pressure to rise. This is more representative of real IC engines, where intermittent combustion takes place. The combustion models are implemented in a commercial computational fluid dynamics (CFD) code, STAR-CD, and it is shown that both strained and unstrained flamelet models are able to predict the experimental pressure rise in a closed vessel.
In the final part of this work, a spark-ignition engine is simulated in STAR-CD using the flamelet model verified for…
Subjects/Keywords: Computational fluid dynamics; Turbulent combustion; Spark-ignition engines
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Export
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APA (6th Edition):
Ahmed, I. (2014). Simulation of turbulent flames relevant to spark-ignition engines. (Doctoral Dissertation). University of Cambridge. Retrieved from https://www.repository.cam.ac.uk/handle/1810/245288https://www.repository.cam.ac.uk/bitstream/1810/245288/2/license.txt ; https://www.repository.cam.ac.uk/bitstream/1810/245288/3/license_rdf ; https://www.repository.cam.ac.uk/bitstream/1810/245288/4/thesis_ahmed.pdf.txt ; https://www.repository.cam.ac.uk/bitstream/1810/245288/5/thesis_ahmed.pdf.jpg
Chicago Manual of Style (16th Edition):
Ahmed, Irufan. “Simulation of turbulent flames relevant to spark-ignition engines.” 2014. Doctoral Dissertation, University of Cambridge. Accessed April 13, 2021.
https://www.repository.cam.ac.uk/handle/1810/245288https://www.repository.cam.ac.uk/bitstream/1810/245288/2/license.txt ; https://www.repository.cam.ac.uk/bitstream/1810/245288/3/license_rdf ; https://www.repository.cam.ac.uk/bitstream/1810/245288/4/thesis_ahmed.pdf.txt ; https://www.repository.cam.ac.uk/bitstream/1810/245288/5/thesis_ahmed.pdf.jpg.
MLA Handbook (7th Edition):
Ahmed, Irufan. “Simulation of turbulent flames relevant to spark-ignition engines.” 2014. Web. 13 Apr 2021.
Vancouver:
Ahmed I. Simulation of turbulent flames relevant to spark-ignition engines. [Internet] [Doctoral dissertation]. University of Cambridge; 2014. [cited 2021 Apr 13].
Available from: https://www.repository.cam.ac.uk/handle/1810/245288https://www.repository.cam.ac.uk/bitstream/1810/245288/2/license.txt ; https://www.repository.cam.ac.uk/bitstream/1810/245288/3/license_rdf ; https://www.repository.cam.ac.uk/bitstream/1810/245288/4/thesis_ahmed.pdf.txt ; https://www.repository.cam.ac.uk/bitstream/1810/245288/5/thesis_ahmed.pdf.jpg.
Council of Science Editors:
Ahmed I. Simulation of turbulent flames relevant to spark-ignition engines. [Doctoral Dissertation]. University of Cambridge; 2014. Available from: https://www.repository.cam.ac.uk/handle/1810/245288https://www.repository.cam.ac.uk/bitstream/1810/245288/2/license.txt ; https://www.repository.cam.ac.uk/bitstream/1810/245288/3/license_rdf ; https://www.repository.cam.ac.uk/bitstream/1810/245288/4/thesis_ahmed.pdf.txt ; https://www.repository.cam.ac.uk/bitstream/1810/245288/5/thesis_ahmed.pdf.jpg
Michigan Technological University
17.
Zhang, Anqi.
COMBUSTION INITIATION BY ELECTRICAL-DISCHARGE-INDUCED PLASMA IN LEAN AND DILUTE METHANE-AIR MIXTURE: EXPERIMENTAL AND MODELING INVESTIGATION.
Degree: PhD, Department of Mechanical Engineering-Engineering Mechanics, 2014, Michigan Technological University
URL: https://digitalcommons.mtu.edu/etd-restricted/220
► This dissertation represents experimental and numerical investigations of combustion initiation trigged by electrical-discharge-induced plasma within lean and dilute methane air mixture. This research topic…
(more)
▼ This dissertation represents experimental and numerical investigations of
combustion initiation trigged by electrical-discharge-induced plasma within lean and dilute methane air mixture. This research topic is of interest due to its potential to further promote the understanding and prediction of
spark ignition quality in high efficiency gasoline engines, which operate with lean and dilute fuel-air mixture.
It is specified in this dissertation that the plasma to flame transition is the key process during the
spark ignition event, yet it is also the most complicated and least understood procedure. Therefore the investigation is focused on the overlapped periods when plasma and flame both exists in the system.
Experimental study is divided into two parts. Experiments in Part I focuses on the flame kernel resulting from the electrical discharge. A number of external factors are found to affect the growth of the flame kernel, resulting in complex correlations between discharge and flame kernel. Heat loss from the flame kernel to code ambient is found to be a dominant factor that quenches the flame kernel. Another experimental focus is on the plasma channel. Electrical discharges into gases induce intense and highly transient plasma. Detailed observation of the size and contents of the discharge-induced plasma channel is performed.
Given the complex correlation and the multi-discipline physical/chemical processes involved in the plasma-flame transition, the modeling principle is taken to reproduce detailed transitions numerically with minimum analytical assumptions. Detailed measurement obtained from experimental work facilitates the more accurate description of initial reaction conditions. The novel and unique
spark source considering both energy and species deposition is defined in a justified manner, which is the key feature of this
Ignition by Plasma (IBP) model.
The results of numerical simulation are intuitive and the potential of numerical simulation to better resolve the complex
spark ignition mechanism is presented. Meanwhile, imperfections of the IBP model and numerical simulation have been specified and will address future attentions.
Advisors/Committee Members: Seong-Young Lee.
Subjects/Keywords: CFD; combustion; flame kernel; plasma; reaction mechanism; spark ignition; Mechanical Engineering
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APA ·
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APA (6th Edition):
Zhang, A. (2014). COMBUSTION INITIATION BY ELECTRICAL-DISCHARGE-INDUCED PLASMA IN LEAN AND DILUTE METHANE-AIR MIXTURE: EXPERIMENTAL AND MODELING INVESTIGATION. (Doctoral Dissertation). Michigan Technological University. Retrieved from https://digitalcommons.mtu.edu/etd-restricted/220
Chicago Manual of Style (16th Edition):
Zhang, Anqi. “COMBUSTION INITIATION BY ELECTRICAL-DISCHARGE-INDUCED PLASMA IN LEAN AND DILUTE METHANE-AIR MIXTURE: EXPERIMENTAL AND MODELING INVESTIGATION.” 2014. Doctoral Dissertation, Michigan Technological University. Accessed April 13, 2021.
https://digitalcommons.mtu.edu/etd-restricted/220.
MLA Handbook (7th Edition):
Zhang, Anqi. “COMBUSTION INITIATION BY ELECTRICAL-DISCHARGE-INDUCED PLASMA IN LEAN AND DILUTE METHANE-AIR MIXTURE: EXPERIMENTAL AND MODELING INVESTIGATION.” 2014. Web. 13 Apr 2021.
Vancouver:
Zhang A. COMBUSTION INITIATION BY ELECTRICAL-DISCHARGE-INDUCED PLASMA IN LEAN AND DILUTE METHANE-AIR MIXTURE: EXPERIMENTAL AND MODELING INVESTIGATION. [Internet] [Doctoral dissertation]. Michigan Technological University; 2014. [cited 2021 Apr 13].
Available from: https://digitalcommons.mtu.edu/etd-restricted/220.
Council of Science Editors:
Zhang A. COMBUSTION INITIATION BY ELECTRICAL-DISCHARGE-INDUCED PLASMA IN LEAN AND DILUTE METHANE-AIR MIXTURE: EXPERIMENTAL AND MODELING INVESTIGATION. [Doctoral Dissertation]. Michigan Technological University; 2014. Available from: https://digitalcommons.mtu.edu/etd-restricted/220
Michigan Technological University
18.
Lawyer, Kristina.
Incorporation of Higher Carbon Number Alcohols in Gasoline Blends for Application in Spark-Ignition Engines.
Degree: PhD, Department of Mechanical Engineering-Engineering Mechanics, 2017, Michigan Technological University
URL: https://digitalcommons.mtu.edu/etdr/347
► The 2007 U.S. Renewable Fuel Standard (RFS2) requires an increase in the use of advanced biofuels up to 36 billion gallons by 2022. Higher…
(more)
▼ The 2007 U.S. Renewable Fuel Standard (RFS2) requires an increase in the use of advanced biofuels up to 36 billion gallons by 2022. Higher carbon number alcohols, in addition to cellulosic ethanol and synthetic biofuels, could be used to meet this demand while adhering to the RFS2 corn-based ethanol limitation. Alcohols of carbon numbers 2 through 8 are chosen based on their chemical and engine-related properties.
Blend comparison metrics are developed from automotive industry trends, consumer expectations, U.S. fuel legislation, and engine requirements. The metrics are then used to create scenarios by which to compare higher alcohol fuel blends to traditional ethanol blends. Each scenario details an overall objective and identifies chemical and engine-related properties that are crucial to meeting that objective as fuel criteria.
Fuel blend property prediction methods are adopted from literature and used to calculate both linear and non-linear properties of multi-component blends. Possible combinations of eight alcohols mixed with a gasoline blendstock are calculated and the properties of the theoretical fuel blends are predicted. Blends that meet all of a scenario’s criteria are identified as suitable blends.
Blends of higher carbon number alcohols with gasoline blendstock are identified as optimal blends for each scenario if they meet all of the scenario’s criteria and maximize either energy content, knock resistance, or petroleum displacement. Optimal blends are tested in a
spark-
ignition engine. The effect of higher carbon number alcohols as a fuel component on engine performance and emissions is examined.
Results suggest that
combustion properties of blends of alcohols with carbon numbers from two to six are similar to those of the reference fuel at low and medium engine loads. Properties of blends of alcohols with carbon numbers from two to four are similar to those of the reference fuel even at high loads. However, due to their reduced knock resistance, the suitability of longer chain alcohols, specifically C5 and longer, as blending agents at increased levels is questionable.
Advisors/Committee Members: Jeff Naber, Scott Miers.
Subjects/Keywords: engine; spark-ignition; alcohol; emissions; fuels; Heat Transfer, Combustion
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APA ·
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MLA ·
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Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Lawyer, K. (2017). Incorporation of Higher Carbon Number Alcohols in Gasoline Blends for Application in Spark-Ignition Engines. (Doctoral Dissertation). Michigan Technological University. Retrieved from https://digitalcommons.mtu.edu/etdr/347
Chicago Manual of Style (16th Edition):
Lawyer, Kristina. “Incorporation of Higher Carbon Number Alcohols in Gasoline Blends for Application in Spark-Ignition Engines.” 2017. Doctoral Dissertation, Michigan Technological University. Accessed April 13, 2021.
https://digitalcommons.mtu.edu/etdr/347.
MLA Handbook (7th Edition):
Lawyer, Kristina. “Incorporation of Higher Carbon Number Alcohols in Gasoline Blends for Application in Spark-Ignition Engines.” 2017. Web. 13 Apr 2021.
Vancouver:
Lawyer K. Incorporation of Higher Carbon Number Alcohols in Gasoline Blends for Application in Spark-Ignition Engines. [Internet] [Doctoral dissertation]. Michigan Technological University; 2017. [cited 2021 Apr 13].
Available from: https://digitalcommons.mtu.edu/etdr/347.
Council of Science Editors:
Lawyer K. Incorporation of Higher Carbon Number Alcohols in Gasoline Blends for Application in Spark-Ignition Engines. [Doctoral Dissertation]. Michigan Technological University; 2017. Available from: https://digitalcommons.mtu.edu/etdr/347
19.
Ahmed, Irufan.
Simulation of turbulent flames relevant to spark-ignition engines.
Degree: PhD, 2014, University of Cambridge
URL: https://doi.org/10.17863/CAM.14074
;
https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.607579
► Combustion research currently aims to reduce emissions, whilst improving the fuel economy. Burning fuel in excess of air, or lean-burn combustion, is a promising alternative…
(more)
▼ Combustion research currently aims to reduce emissions, whilst improving the fuel economy. Burning fuel in excess of air, or lean-burn combustion, is a promising alternative to conventional combustion, and can achieve these requirements simultaneously. However, lean-burn combustion poses new challenges, especially for internal combustion (IC) engines. Therefore, models used to predict such combustion have to be reliable, accurate and robust. In this work, the flamelet approach in the Reynolds-Averaged Navier- Stokes framework, is used to simulate flames relevant to spark-ignition IC engines. A central quantity in the current modelling approach is the scalar dissipation rate, which represents coupling between reaction and diffusion, as well as the flame front dynamics. In the first part of this thesis, the predictive ability of two reaction rate closures, viz. strained and unstrained flamelet models, are assessed through a series of experimental test cases. These cases are: spherically propagating methane- and hydrogen-air flames and combustion in a closed vessel. In addition to these models, simpler algebraic closures are also used for comparison. It is shown that the strained flamelet model can predict unconfined, spherically propagating methane-air flames reasonably well. By comparing spherical flame results with planar flames, under identical thermochemical and turbulence conditions, it is shown that the turbulent flame speed of spherical flames are 10 to 20% higher than that of planar flames, whilst the mean reaction rates are less influenced by the flame geometry. Growth of the flame brush thickness in unsteady spherical flames have been attributed to turbulent diffusion in past studies. However, the present analyses revealed that the dominant cause for this increase is the heat-release induced convective effects, which is a novel observation. Unlike methane-air flames, hydrogen-air flames have non-unity Lewis numbers. Hence, a novel two degrees of freedom approach, using two progress variables, is used to describe the thermochemistry of hydrogen-air flames. Again, it is shown that the strained flamelet model is able to predict the experimental flame growth for stoichiometric hydrogen-air flames. However, none of the models used in this work were able to predict lean hydrogen-air flames. This is because these flames are thermo-diffusively unstable and the current approach is inadequate to represent them. When combustion takes place inside a closed vessel, the compression of the end gases by the propagating flame causes the pressure to rise. This is more representative of real IC engines, where intermittent combustion takes place. The combustion models are implemented in a commercial computational fluid dynamics (CFD) code, STAR-CD, and it is shown that both strained and unstrained flamelet models are able to predict the experimental pressure rise in a closed vessel. In the final part of this work, a spark-ignition engine is simulated in STAR-CD using the flamelet model verified for simpler geometries. It is…
Subjects/Keywords: 621.402; Computational fluid dynamics; Turbulent combustion; Spark-ignition engines
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APA (6th Edition):
Ahmed, I. (2014). Simulation of turbulent flames relevant to spark-ignition engines. (Doctoral Dissertation). University of Cambridge. Retrieved from https://doi.org/10.17863/CAM.14074 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.607579
Chicago Manual of Style (16th Edition):
Ahmed, Irufan. “Simulation of turbulent flames relevant to spark-ignition engines.” 2014. Doctoral Dissertation, University of Cambridge. Accessed April 13, 2021.
https://doi.org/10.17863/CAM.14074 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.607579.
MLA Handbook (7th Edition):
Ahmed, Irufan. “Simulation of turbulent flames relevant to spark-ignition engines.” 2014. Web. 13 Apr 2021.
Vancouver:
Ahmed I. Simulation of turbulent flames relevant to spark-ignition engines. [Internet] [Doctoral dissertation]. University of Cambridge; 2014. [cited 2021 Apr 13].
Available from: https://doi.org/10.17863/CAM.14074 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.607579.
Council of Science Editors:
Ahmed I. Simulation of turbulent flames relevant to spark-ignition engines. [Doctoral Dissertation]. University of Cambridge; 2014. Available from: https://doi.org/10.17863/CAM.14074 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.607579
The Ohio State University
20.
Frederick, John David.
Time-Resolved In-Cylinder Heat Transfer and its Implications
on Knock in Spark Ignition Engines.
Degree: MS, Mechanical Engineering, 2015, The Ohio State University
URL: http://rave.ohiolink.edu/etdc/view?acc_num=osu1437648508
► Spark Ignition (SI) engines power 96.6% of light duty vehicles produced in North America in 2013, yet the ability to increase their efficiency through strategies…
(more)
▼ Spark Ignition (SI) engines power 96.6% of light duty
vehicles produced in North America in 2013, yet the ability to
increase their efficiency through strategies such as boosting or
increasing the
compression ratio is limited by knock. Knock, or the
autoignition of the fuel and air mixture ahead of the flame front,
is dictated by chemical kinetics and the rates of the reactions
leading to autoignition are determined by the Boltzmann factor,
which is exponentially dependent on the local gas temperature. The
gas temperature is a function of both the heat release from
combustion and the in-cylinder heat transfer. Therefore, to predict
knock and operate SI engines as efficiently as possible, it is
necessary to accurately model the in-cylinder heat transfer
process. Hence, the objective of the present study is to improve
the understanding of in-cylinder heat transfer of SI
engines.Time-resolved in-cylinder heat transfer was measured in
cylinder4 of a Chrysler 2.0L I4 engine using Vatell Heat Flux
Microsensors (HFMs) along with pressure measurements within the
combustion chamber and in the intake runner and plenum as well as
the exhaust runner. Firing engine experiments were first performed
with a single heat flux sensor at 1600 and 2400 RPM wide open
throttle (WOT). Carbon deposits built up on the HFM surface,
necessitating the development of a sensor cleaning procedure using
acetone as a solvent. An approximate pressure limit of 50 bar for
the HFM was also determined with this cylinder head. Motored engine
experiments were then performed with a multi-sensor cylinder head
with two HFMs at 1200, 1600, 2000, 2400, and 3000 RPM WOT and the
peak heat flux was observed to increase with increasing engine
speed. Despite negligible variation of the in-cylinder pressure
from cycle-to-cycle, cyclic variation of heat flux was significant
at both measurement locations. Firing experiments with the
multi-sensor cylinder head were completed at 1200, 1600, and 2000
RPM WOT. Significant spatial differences in heat flux were observed
between the two measurement locations for firing operation. Peak
heat flux measured between the intake and exhaust valves (HFM3) was
49% higher on average than at the intake bridge (HFM1) while also
reaching peak magnitude earlier. Average flame propagation speeds
in the direction of HFM3 were on average 46% higher than towards
HFM1 as well. Similar to the motored experiments, high cyclic
variability of heat flux was observed for all firing experiments.
Even with considerable cycle-to-cycle variation, average
in-cylinder pressure and heat flux measurements were found to be
quite repeatable.Detailed 3D CFD simulations of cylinder #4 for
motored and firing operation were performed at 1600 RPM WOT using
CONVERGE CFD software. Predicted pressure and heat flux for motored
operation matched the experimental results well. For the firing
engine,
combustion was modeled using a kinetics mechanism for a
primary reference fuel blend (PRF 91). Both the predicted cylinder
pressure and heat flux showed good agreement with…
Advisors/Committee Members: Selamet, Ahmet (Advisor).
Subjects/Keywords: Mechanical Engineering; Knock; Heat Transfer; Spark Ignition Engines; Combustion
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Frederick, J. D. (2015). Time-Resolved In-Cylinder Heat Transfer and its Implications
on Knock in Spark Ignition Engines. (Masters Thesis). The Ohio State University. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=osu1437648508
Chicago Manual of Style (16th Edition):
Frederick, John David. “Time-Resolved In-Cylinder Heat Transfer and its Implications
on Knock in Spark Ignition Engines.” 2015. Masters Thesis, The Ohio State University. Accessed April 13, 2021.
http://rave.ohiolink.edu/etdc/view?acc_num=osu1437648508.
MLA Handbook (7th Edition):
Frederick, John David. “Time-Resolved In-Cylinder Heat Transfer and its Implications
on Knock in Spark Ignition Engines.” 2015. Web. 13 Apr 2021.
Vancouver:
Frederick JD. Time-Resolved In-Cylinder Heat Transfer and its Implications
on Knock in Spark Ignition Engines. [Internet] [Masters thesis]. The Ohio State University; 2015. [cited 2021 Apr 13].
Available from: http://rave.ohiolink.edu/etdc/view?acc_num=osu1437648508.
Council of Science Editors:
Frederick JD. Time-Resolved In-Cylinder Heat Transfer and its Implications
on Knock in Spark Ignition Engines. [Masters Thesis]. The Ohio State University; 2015. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=osu1437648508
Georgia Tech
21.
Lambert, Alexander.
LES of Turbulent Premixed Flame Kernel Formation and Development.
Degree: MS, Aerospace Engineering, 2020, Georgia Tech
URL: http://hdl.handle.net/1853/64079
► Spark ignition of flammable mixtures is highly sensitive to early and local conditions. Kernel formation and subsequent flame development are largely governed by turbulent conditions…
(more)
▼ Spark ignition of flammable mixtures is highly sensitive to early and local conditions. Kernel formation and subsequent flame development are largely governed by turbulent conditions and interactions with igniter geometry. In order to investigate this phenomenon, the use of Large Eddy Simulation (LES) is examined for (1) modelling spherical turbulent flame development, and (2) simulating
spark ignition in a channel with either laminar or turbulent inflow.
A comparison between LES spherical flame simulation is made to FSD-LES results as well as experimental measurements from previous studies.
For
spark ignition experiments, we characterize the temporal evolution of the
ignition process, and demonstrate the dependence on early velocity fluctuations and local conditions.
Advisors/Committee Members: Menon, Suresh (advisor), Seitzman, Jerry (committee member), Jagoda, Jechiel (committee member).
Subjects/Keywords: Large Eddy Simulation; Spark Ignition; Turbulent Combustion; Computational Fluid Dynamics
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APA (6th Edition):
Lambert, A. (2020). LES of Turbulent Premixed Flame Kernel Formation and Development. (Masters Thesis). Georgia Tech. Retrieved from http://hdl.handle.net/1853/64079
Chicago Manual of Style (16th Edition):
Lambert, Alexander. “LES of Turbulent Premixed Flame Kernel Formation and Development.” 2020. Masters Thesis, Georgia Tech. Accessed April 13, 2021.
http://hdl.handle.net/1853/64079.
MLA Handbook (7th Edition):
Lambert, Alexander. “LES of Turbulent Premixed Flame Kernel Formation and Development.” 2020. Web. 13 Apr 2021.
Vancouver:
Lambert A. LES of Turbulent Premixed Flame Kernel Formation and Development. [Internet] [Masters thesis]. Georgia Tech; 2020. [cited 2021 Apr 13].
Available from: http://hdl.handle.net/1853/64079.
Council of Science Editors:
Lambert A. LES of Turbulent Premixed Flame Kernel Formation and Development. [Masters Thesis]. Georgia Tech; 2020. Available from: http://hdl.handle.net/1853/64079
Brunel University
22.
Bureshaid, Khalifa.
A study of turbulent jet ignition combustion in an optical research engine with alternative fuels.
Degree: PhD, 2019, Brunel University
URL: http://bura.brunel.ac.uk/handle/2438/20076
;
https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.814396
► Turbulent Jet Ignition (TJI) is an advanced ignition process where ultra-lean mixtures can ignite in standard gasoline spark ignition engine. In this research, a TJI…
(more)
▼ Turbulent Jet Ignition (TJI) is an advanced ignition process where ultra-lean mixtures can ignite in standard gasoline spark ignition engine. In this research, a TJI unit by Mahle Powertrain USA was adopted and studied in a bespoke single-cylinder engine with optical acess. The TJI device features a very small pre-chamber that is connected to the main chamber by multiple small orifices and can be separately fuelled by a direct fuel injector. The spark plug shifts from the main chamber to the pre-chamber to ignite the pre-chamber mixture. A new cylinder head was designed and manufactured to accommodate the TJI unit and optical windows on the top and sides of the cylinder head block. A new direct inejector (DI) fuel supply system was set up for direct fuel injection in the pre-chamber. A new engine control and a data system were commissioned and used for engine experiments and heat release analysis. High-speed combustion imaging and spectroscopic techniques were developed to study the ignition and combustion in the main chamber through high-speed cameras and spectrographic equipment. Thermodynamic studies on TJI combustion in a single-cylinder engine demonstrate the ability of TJI to extend the lean-burn limit of gasoline operation at different engine speeds and loads. Similar effects are also observed with engine operations fuelled with ethanol and wet-ethanol. TJI exerts the greatest effect in extending the lean-burn limit of ethanol fuel and leads to near-zero NOx emissions near the lean-burn limit. In addition, the TJI ethanol engine operation has higher thermal efficiency as well as lower HC and CO emissions than the gasoline operation. Spectroscopic results reveal that ethanol combustion produces higher chemiluminescent emissions than gasoline during the normal spark ignition combustion in the main chamber. The OH spectral peak at 310 nm is the highest throughout the ignition and combustion, followed by CH emission at 430 nm and HCO at 330 nm. Their intensities peak before the maximum heat release rates measured by the in-cylinder pressure. Emission spectra produced by the pre-chamber ignition are stronger than the normal spark ignition in the main chamber. The highest emission intensities are observed with the fuelled pre-chamber ignition even with leaner air–fuel mixture in the main chamber. As pre-chamber fuel is increased, the pre-chamber pressure rises faster to a higher peak value, producing greater pressure differential between the pre-chamber and main chamber and faster turbulent jets of partially burned products at higher temperature. The increase in the pre-chamber pressure causes the jets to travel deeper into the main chamber and enlarges the ignition sites. In addition, the ignition delay of the main chamber combustion is shortened due to the higher temperature of turbulent jets, as indicated by the stonger emission spectra. The turbulent ignition jets of ethanol are characterised with greater momentum than gasoline due to the faster combustion speed of ethanol and higher energy input. When the…
Subjects/Keywords: Mahle Jet Ignition (MJI); Spark Ignition (SI); Stratified change engine; Lean burning; The hydrogen-assisted jet ignition (HAJI)
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MLA ·
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Manager
APA (6th Edition):
Bureshaid, K. (2019). A study of turbulent jet ignition combustion in an optical research engine with alternative fuels. (Doctoral Dissertation). Brunel University. Retrieved from http://bura.brunel.ac.uk/handle/2438/20076 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.814396
Chicago Manual of Style (16th Edition):
Bureshaid, Khalifa. “A study of turbulent jet ignition combustion in an optical research engine with alternative fuels.” 2019. Doctoral Dissertation, Brunel University. Accessed April 13, 2021.
http://bura.brunel.ac.uk/handle/2438/20076 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.814396.
MLA Handbook (7th Edition):
Bureshaid, Khalifa. “A study of turbulent jet ignition combustion in an optical research engine with alternative fuels.” 2019. Web. 13 Apr 2021.
Vancouver:
Bureshaid K. A study of turbulent jet ignition combustion in an optical research engine with alternative fuels. [Internet] [Doctoral dissertation]. Brunel University; 2019. [cited 2021 Apr 13].
Available from: http://bura.brunel.ac.uk/handle/2438/20076 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.814396.
Council of Science Editors:
Bureshaid K. A study of turbulent jet ignition combustion in an optical research engine with alternative fuels. [Doctoral Dissertation]. Brunel University; 2019. Available from: http://bura.brunel.ac.uk/handle/2438/20076 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.814396
Brno University of Technology
23.
Krejčí, Tomáš.
Mazání vznětových a zážehových motorů: Lubrication of gasoline and diesel engines.
Degree: 2019, Brno University of Technology
URL: http://hdl.handle.net/11012/997
► The main subject of this bachelor’s thesis is describing the present state of knowledge in the sphere of compression-ignition and spark-ignition engines lubrication, lubricants and…
(more)
▼ The main
subject of this bachelor’s thesis is describing the present state of knowledge in the sphere of
compression-
ignition and
spark-
ignition engines lubrication, lubricants and future trends. First part is about internal
combustion principle, engine construction. Next parts are about engine lubrication system, lubricating modes, and its locating in the engine. Last part is about oils, and insights into the future.
Advisors/Committee Members: Křupka, Ivan (advisor), Vaverka, Michal (referee).
Subjects/Keywords: vznětový motor; zážehový motor; vnitřní spalování; olejové hospodářství; mazání; mezné tření; hydrodynamické tření; motorové oleje; aditiva; compression-ignition engine; spark-ignition engine; internal combustion; engine lubrication system; lubricating; boundary lubrication; hydrodynamic lubrication; oils; additives
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APA (6th Edition):
Krejčí, T. (2019). Mazání vznětových a zážehových motorů: Lubrication of gasoline and diesel engines. (Thesis). Brno University of Technology. Retrieved from http://hdl.handle.net/11012/997
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Krejčí, Tomáš. “Mazání vznětových a zážehových motorů: Lubrication of gasoline and diesel engines.” 2019. Thesis, Brno University of Technology. Accessed April 13, 2021.
http://hdl.handle.net/11012/997.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Krejčí, Tomáš. “Mazání vznětových a zážehových motorů: Lubrication of gasoline and diesel engines.” 2019. Web. 13 Apr 2021.
Vancouver:
Krejčí T. Mazání vznětových a zážehových motorů: Lubrication of gasoline and diesel engines. [Internet] [Thesis]. Brno University of Technology; 2019. [cited 2021 Apr 13].
Available from: http://hdl.handle.net/11012/997.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Krejčí T. Mazání vznětových a zážehových motorů: Lubrication of gasoline and diesel engines. [Thesis]. Brno University of Technology; 2019. Available from: http://hdl.handle.net/11012/997
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of New South Wales
24.
Woo, Changhwan.
Combustion strategies for the increased use of biofuels in a small-bore diesel engine.
Degree: Mechanical & Manufacturing Engineering, 2015, University of New South Wales
URL: http://handle.unsw.edu.au/1959.4/55382
;
https://unsworks.unsw.edu.au/fapi/datastream/unsworks:37427/SOURCE02?view=true
► Biodiesel and ethanol are most widely considered as a promising alternative fuel to petroleum diesel and gasoline due to their renewable nature and potential reduction…
(more)
▼ Biodiesel and ethanol are most widely considered as a promising alternative fuel to petroleum diesel and gasoline due to their renewable nature and potential reduction in greenhouse gas emissions. This thesis applies three different
combustion strategies that can achieve the increased use of these biofuels without compromising engine efficiency and pollutant emissions, which includes 1) coconut oil-based biodiesel
combustion with varying blending ratios of biodiesel and petroleum diesel, 2) dual-fuel
combustion of port injected ethanol and direct injected biodiesel blend, and 3) neat ethanol
combustion in a common-rail diesel engine. All of the three
combustion strategies are realised in the same single-cylinder light-duty diesel engine. For the coconut-oil biodiesel
combustion, a higher biodiesel blending ratio results in decreased indicated power but the improved lubricity of coconut-oil biodiesel and hence reduced friction loses leads to similar brake power of diesel. From the engine-out emissions, a significant reduction of smoke emissions are observed with an increase in the biodiesel blending ratio, which is explained by the oxygenated molecular structures and reduced aromatics contents of biodiesel. Also, the slower reaction and leaner mixture of high biodiesel blends, together with shorter carbon chain length of coconut-oil biodiesel, cause the reduced flame temperature and thereby decreasing NOx emissions. Nevertheless, a significant increase in the brake specific fuel consumption limits the highest biodiesel blending ratio at B40. The increased use of biofuel is achieved via an alternative approach using dual-fuelling of ethanol and B40. The results show that the indicated power increases with increasing ethanol energy fraction because the increased premixed charge leads to faster burning and thereby increasing the heat release rate. This effect, together with the reduced friction loss of coconut-oil biodiesel, results in higher brake power than diesel
combustion while both smoke and NOx emissions are significantly reduced. The most promising results are found when neat ethanol is injected directly into the cylinder using a common-rail system, which achieve 100% biofuel usage. The optimised injection strategy using a split injection comprised of early bottom-dead-centre injection and near top-dead-centre injection achieves 50% higher fuel conversion efficiency despite 5% lower brake specific fuel consumption. The NOx emissions are reduced 30% while smoke emission is negligible.
Advisors/Committee Members: Sanghoon, Kook, Mechanical & Manufacturing Engineering, Faculty of Engineering, UNSW, Qing Nian (Shaun), Chan, Mechanical & Manufacturing Engineering, Faculty of Engineering, UNSW.
Subjects/Keywords: Emissions; Gasoline compression ignition; Partially premixed combustion; Gasoline compression ignition; Biofuel; Diesel engine; Partially premixed combustion
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MLA ·
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APA (6th Edition):
Woo, C. (2015). Combustion strategies for the increased use of biofuels in a small-bore diesel engine. (Doctoral Dissertation). University of New South Wales. Retrieved from http://handle.unsw.edu.au/1959.4/55382 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:37427/SOURCE02?view=true
Chicago Manual of Style (16th Edition):
Woo, Changhwan. “Combustion strategies for the increased use of biofuels in a small-bore diesel engine.” 2015. Doctoral Dissertation, University of New South Wales. Accessed April 13, 2021.
http://handle.unsw.edu.au/1959.4/55382 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:37427/SOURCE02?view=true.
MLA Handbook (7th Edition):
Woo, Changhwan. “Combustion strategies for the increased use of biofuels in a small-bore diesel engine.” 2015. Web. 13 Apr 2021.
Vancouver:
Woo C. Combustion strategies for the increased use of biofuels in a small-bore diesel engine. [Internet] [Doctoral dissertation]. University of New South Wales; 2015. [cited 2021 Apr 13].
Available from: http://handle.unsw.edu.au/1959.4/55382 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:37427/SOURCE02?view=true.
Council of Science Editors:
Woo C. Combustion strategies for the increased use of biofuels in a small-bore diesel engine. [Doctoral Dissertation]. University of New South Wales; 2015. Available from: http://handle.unsw.edu.au/1959.4/55382 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:37427/SOURCE02?view=true
University of Kansas
25.
Srivatsa, Charu Vikram Chandrashekhar.
Performance and Emissions Analysis of Pre-mixed and Partially Pre-mixed Charge Compression Ignition Combustion.
Degree: MS, Mechanical Engineering, 2017, University of Kansas
URL: http://hdl.handle.net/1808/24133
► Due to raising concerns of depleting petroleum reserves coupled with global warming, the interest in Compression Ignition (CI) engines is more than ever primarily due…
(more)
▼ Due to raising concerns of depleting petroleum reserves coupled with global warming, the interest in
Compression Ignition (CI) engines is more than ever primarily due to the comparatively superior efficiency of CI engines over
Spark Ignition (SI) engines. However, nitrogen oxides (NOx) and Particulate Matter (PM) emissions, and the nature of their trade-off is a major hurdle for CI engines to meet the future emissions regulations. In the last two decades, Low Temperature
Combustion (LTC), a method stated to be effective in reducing both NOx and PM emissions simultaneously, has received justifiable attention. In this thesis, the importance of mitigating various emissions from CI engines and the relevant challenges is presented in Chapter 1. Subsequently, brief literature reviews of the various types of LTC; namely, Homogeneous Charge
Compression Ignition (HCCI), Pre-mixed Charge
Compression Ignition (PCI), and Multi-point Fuel Injection (MPFI) are included in Chapter 2. Details of the single cylinder CI engine lab facility at the University of Kansas (KU) are given in Chapter 3. Additionally, performance and emissions results of a PCI
combustion trial are presented. Here, the fuel injection timing was modified at various stages to shift from conventional to PCI
combustion regime. Based on the results obtained, a follow up experimental study similar to the previous one was conducted to explore the advantages and restrictions of Partially Pre-mixed
Compression Ignition (PPCI)
combustion (Chapter 4). Furthermore, an in house built zero-dimensional heat release model was utilized to analyze the in-cylinder pressure data of both the tests conducted. In general, the performance, emissions, and heat release model results indicated good agreement with the trends published in the literature.
Advisors/Committee Members: Depcik, Christopher (advisor), Kwon, Gibum (cmtemember), Fang, Huazheng (cmtemember).
Subjects/Keywords: Engineering; Energy; Mechanical engineering; Compression ratio; Environmental emissions; Internal combustion engine; Low temmperature combustion; Partially pre-mixed charge compression ignition combustion; Pre-mixed charge compression ignition combustion
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APA ·
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MLA ·
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Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Srivatsa, C. V. C. (2017). Performance and Emissions Analysis of Pre-mixed and Partially Pre-mixed Charge Compression Ignition Combustion. (Masters Thesis). University of Kansas. Retrieved from http://hdl.handle.net/1808/24133
Chicago Manual of Style (16th Edition):
Srivatsa, Charu Vikram Chandrashekhar. “Performance and Emissions Analysis of Pre-mixed and Partially Pre-mixed Charge Compression Ignition Combustion.” 2017. Masters Thesis, University of Kansas. Accessed April 13, 2021.
http://hdl.handle.net/1808/24133.
MLA Handbook (7th Edition):
Srivatsa, Charu Vikram Chandrashekhar. “Performance and Emissions Analysis of Pre-mixed and Partially Pre-mixed Charge Compression Ignition Combustion.” 2017. Web. 13 Apr 2021.
Vancouver:
Srivatsa CVC. Performance and Emissions Analysis of Pre-mixed and Partially Pre-mixed Charge Compression Ignition Combustion. [Internet] [Masters thesis]. University of Kansas; 2017. [cited 2021 Apr 13].
Available from: http://hdl.handle.net/1808/24133.
Council of Science Editors:
Srivatsa CVC. Performance and Emissions Analysis of Pre-mixed and Partially Pre-mixed Charge Compression Ignition Combustion. [Masters Thesis]. University of Kansas; 2017. Available from: http://hdl.handle.net/1808/24133
Penn State University
26.
Kalaskar, Vickey Baliram.
Ignition Behavior of Gasolines and Surrogate Fuels in Low Temperature Combustion Strategies.
Degree: 2015, Penn State University
URL: https://submit-etda.libraries.psu.edu/catalog/25975
► This dissertation discusses the results from three different studies aimed at understanding the importance of fuel chemical structure during low temperature combustion (LTC) strategies, like…
(more)
▼ This dissertation discusses the results from three different studies aimed at understanding the importance of fuel chemical structure during low temperature
combustion (LTC) strategies, like homogeneous charge
compression ignition (HCCI) and partially premixed
combustion (PPC) employed in internal
combustion (IC) engines wherein the focus is on high octane fuels.
Boosted intake air operation combined with exhaust gas recirculation, internal as well as external, has become a standard path for expanding the load limits of IC engines employing LTC strategies mentioned above as well as conventional diesel and
spark ignition (SI) engines. However, the effects of fuel compositional variation have not been fully explored. The first study focusses on three different fuels, where each of them were evaluated using a single cylinder boosted HCCI engine using negative valve overlap. The three fuels investigated were: a regular grade gasoline (RON = 90.2), 30% ethanol-gasoline blend (E30, RON = 100.3), and 24% iso-butanol-gasoline blend (IB24, RON = 96.6). Detailed sweeps of intake manifold pressure (atmospheric to 250 kPaa), EGR (0 – 25% EGR), and injection timing were conducted to identify fuel-specific effects. While significant fuel compositional differences existed, the results showed that all these fuels achieved comparable operation with minor changes in operational conditions. Further, it was shown that the available enthalpy from the exhaust would not be sufficient to satisfy the boost requirements at higher load operation by doing an analysis of the required turbocharger efficiency.
While the first study concentrated on load expansion of HCCI, it is important to mention that controlling LTC strategies is difficult under low load or idle operating conditions. To ensure stable operation, fuel injection in the negative valve overlap (NVO) is used as one of method of achieving
combustion control. However the
combustion chemistry under high temperature and fuel rich conditions that exist during the NVO have not been previously explored. The second study focused on examining the products of fuel rich chemistry as a result of fuel injection in the NVO. In this study, a unique six stroke cycle was used to segregate the exhaust from the NVO and to study the chemistry of the range of fuels injected during NVO under low oxygen conditions. The fuels investigated were methanol, ethanol, iso-butanol, and iso-octane. It was observed that the products of reactions under NVO conditions were highly dependent on the injected fuel’s structure with iso-octane producing less than 1.5% hydrogen and methanol producing more than 8%. However a weak dependence was observed on NVO duration and initial temperature, indicating that NVO reforming was kinetically limited. Finally, the experimental trends were compared with CHEMKIN (single zone, 0-D model) predictions using multiple kinetic mechanism that were readily available through literature. Due to the simplicity of the model and inadequate information on the fuel injection process, the…
Advisors/Committee Members: Andre Louis Boehman, Dissertation Advisor/Co-Advisor, Randy Vander Wal, Dissertation Advisor/Co-Advisor, Chunshan Song, Committee Member, Daniel Connell Haworth, Committee Member, James Szybist, Special Member.
Subjects/Keywords: Autoignition; Combustion; Compression ignition; Negative valve overlap; Ignition behavior; LTC; HCCI; PPC
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APA (6th Edition):
Kalaskar, V. B. (2015). Ignition Behavior of Gasolines and Surrogate Fuels in Low Temperature Combustion Strategies. (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/25975
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Kalaskar, Vickey Baliram. “Ignition Behavior of Gasolines and Surrogate Fuels in Low Temperature Combustion Strategies.” 2015. Thesis, Penn State University. Accessed April 13, 2021.
https://submit-etda.libraries.psu.edu/catalog/25975.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Kalaskar, Vickey Baliram. “Ignition Behavior of Gasolines and Surrogate Fuels in Low Temperature Combustion Strategies.” 2015. Web. 13 Apr 2021.
Vancouver:
Kalaskar VB. Ignition Behavior of Gasolines and Surrogate Fuels in Low Temperature Combustion Strategies. [Internet] [Thesis]. Penn State University; 2015. [cited 2021 Apr 13].
Available from: https://submit-etda.libraries.psu.edu/catalog/25975.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Kalaskar VB. Ignition Behavior of Gasolines and Surrogate Fuels in Low Temperature Combustion Strategies. [Thesis]. Penn State University; 2015. Available from: https://submit-etda.libraries.psu.edu/catalog/25975
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of New South Wales
27.
Goyal, Harsh.
Double injection strategy in a small-bore gasoline compression ignition engine.
Degree: Mechanical & Manufacturing Engineering, 2019, University of New South Wales
URL: http://handle.unsw.edu.au/1959.4/62702
;
https://unsworks.unsw.edu.au/fapi/datastream/unsworks:59141/SOURCE02?view=true
► Gasoline compression ignition (GCI) engines achieve higher engine efficiency and lower NOx/soot emissions than diesel compression ignition engines through partially premixed charge combustion. The thesis…
(more)
▼ Gasoline
compression ignition (GCI) engines achieve higher engine efficiency and lower NOx/soot emissions than diesel
compression ignition engines through partially premixed charge
combustion. The thesis aims to evaluate double-injection strategies for GCI
combustion, their effects on efficiency/emissions, and
ignition process. Two engines were used: a single-cylinder metal engine for performance/emissions testing and an optical engine sharing the same geometry. From the performance/emissions tests, it was shown that the double-injection strategy implementing early near-BDC and late near-TDC injections shows higher efficiency and lower emissions than the single-injection strategy. The GCI
combustion showed high sensitivity to advanced second injection timing with advanced
combustion phasing leading to increased engine efficiency, reduced smoke/uHC/CO emissions but higher noise and NOx. For fixed
combustion phasing, the increased first injection proportion causes lower peak heat release rate due to increased homogeneity of the first-injection charge and thereby achieving lower smoke/NOx/noise emissions but higher uHC/CO. Regarding
ignition quality, higher octane fuel at fixed mixture homogeneity showed higher power output due to increased charge premixedness of the second-injection. Given the strong influence to mixture preparation and subsequent
ignition processes, visualisation of
combustion luminosity and OH* chemiluminescence was performed. The results show that single-injection leads to multiple auto-
ignition kernel development from which isolated flame growth occurs while for double-injection, isolated flame growth is not clearly defined due to increased mixture homogeneity. Detailed measurements using PLIF imaging of fuel, HCHO, and OH showed that single-injection leads to low-temperature reaction from bowl-wall region due to extended
ignition delay. The high-temperature reaction also starts from the bowl-wall region; however, this transition involves multiple
ignition kernels that progressively merge to form large high-temperature reaction zones. In comparison, double-injection shows dispersed fuel distribution, higher HCHO consumption rate and faster OH development across all reaction zones, indicating faster low- to high-temperature reaction transition. These fundamental findings explain how double-injection-based GCI
combustion generates less NOx/soot emissions than single-injection while achieving better
combustion stability.
Advisors/Committee Members: Kook, Sanghoon (Shawn), Mechanical & Manufacturing Engineering, Faculty of Engineering, UNSW, Hawkes, Evatt, Mechanical & Manufacturing Engineering, Faculty of Engineering, UNSW.
Subjects/Keywords: Combustion; Gasoline compression ignition (GCI); Double injection strategies
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APA (6th Edition):
Goyal, H. (2019). Double injection strategy in a small-bore gasoline compression ignition engine. (Doctoral Dissertation). University of New South Wales. Retrieved from http://handle.unsw.edu.au/1959.4/62702 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:59141/SOURCE02?view=true
Chicago Manual of Style (16th Edition):
Goyal, Harsh. “Double injection strategy in a small-bore gasoline compression ignition engine.” 2019. Doctoral Dissertation, University of New South Wales. Accessed April 13, 2021.
http://handle.unsw.edu.au/1959.4/62702 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:59141/SOURCE02?view=true.
MLA Handbook (7th Edition):
Goyal, Harsh. “Double injection strategy in a small-bore gasoline compression ignition engine.” 2019. Web. 13 Apr 2021.
Vancouver:
Goyal H. Double injection strategy in a small-bore gasoline compression ignition engine. [Internet] [Doctoral dissertation]. University of New South Wales; 2019. [cited 2021 Apr 13].
Available from: http://handle.unsw.edu.au/1959.4/62702 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:59141/SOURCE02?view=true.
Council of Science Editors:
Goyal H. Double injection strategy in a small-bore gasoline compression ignition engine. [Doctoral Dissertation]. University of New South Wales; 2019. Available from: http://handle.unsw.edu.au/1959.4/62702 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:59141/SOURCE02?view=true
University of Victoria
28.
Pitt, Philip Lawrence.
The early phase of spark ignition.
Degree: Department of Physics and Astronomy, 2018, University of Victoria
URL: https://dspace.library.uvic.ca//handle/1828/9664
► In this dissertation, some practical ignition techniques are presented that show how some problems of lean-burn combustion can be overcome. Then, to shed light on…
(more)
▼ In this dissertation, some practical
ignition techniques are presented that show how some problems of lean-burn
combustion can be overcome. Then, to shed light on the effects of the
ignition techniques described, the focus shifts to the more specific problem of the early phase of
spark ignition. Thermal models of
ignition are reviewed. These models treat the energy provided by the electrical discharge as a point source, delivered infinitely fast and creating a spherically symmetric
ignition kernel. The thesis challenges the basis of these thermal models by reviewing the work of many investigators who have clearly shown that the temporal characteristics of the discharge have a profound effect upon
ignition. Photographic evidence of the early phase of
ignition, as well as other evidence from the literature, is also presented. The evidence clearly demonstrates that the morphology of
spark kernels in the early phase of development is toroidal, not spherical as suggested by thermal models. A new perspective for
ignition, a fluid dynamic point of view, is described. The common
ignition devices are then classified according to fluid dynamics. A model describing the behaviour of
spark kernels is presented, which extends a previously established mixing model for plasma jets, to the realm of conventional axial discharges. Comparison of the model behaviour to some limited data is made. The model is modified by including the effect of heat addition from
combustion, and
ignition criteria are discussed.
Advisors/Committee Members: Clements, R. M. (supervisor).
Subjects/Keywords: Spark ignition engines
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Manager
APA (6th Edition):
Pitt, P. L. (2018). The early phase of spark ignition. (Thesis). University of Victoria. Retrieved from https://dspace.library.uvic.ca//handle/1828/9664
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Pitt, Philip Lawrence. “The early phase of spark ignition.” 2018. Thesis, University of Victoria. Accessed April 13, 2021.
https://dspace.library.uvic.ca//handle/1828/9664.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Pitt, Philip Lawrence. “The early phase of spark ignition.” 2018. Web. 13 Apr 2021.
Vancouver:
Pitt PL. The early phase of spark ignition. [Internet] [Thesis]. University of Victoria; 2018. [cited 2021 Apr 13].
Available from: https://dspace.library.uvic.ca//handle/1828/9664.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Pitt PL. The early phase of spark ignition. [Thesis]. University of Victoria; 2018. Available from: https://dspace.library.uvic.ca//handle/1828/9664
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
29.
Demuynck, Joachim.
A fuel independent heat transfer correlation for premixed spark ignition engines.
Degree: 2012, Ghent University
URL: http://hdl.handle.net/1854/LU-3079977
► Simulation models for internal combustion engines are an indispensable development tool, since engines have become increasingly complex, with many control variables and conflicting optimization targets.…
(more)
▼ Simulation models for internal
combustion engines are an indispensable development tool, since engines have become increasingly complex, with many control variables and conflicting optimization targets. The heat transfer model, which computes the heat losses to the cylinder walls inside the engine is one of the most important sub-models, because it has an influence on the main three optimization targets (efficiency, emissions and power output). Although it is an important sub-model, little progress was reported in recent years due to the lack of accurate heat loss measurements inside an engine. Consequently, heat transfer models have not followed the evolution in engine technology and fuels and there is a need to improve them.
This doctoral research investigated the heat losses in
spark-
ignition engines and focused on the effect of different alternative fuels. First, an accurate heat flux sensor was implemented in a test engine in the lab to measure the heat losses to the walls. This was not a straightforward step, since it is not a mature technology due to the required response and robustness. Second, the sensor was used to build a database of heat flux measurements in the engine which focuses on the effect of the fuel. Special care was devoted to the experimental design, resulting in a unique database which shows that the fuel can significantly affect the amount of heat losses. The obtained database allowed to better understand the heat transfer mechanism inside an internal
combustion engine. Finally, these insights resulted in a new heat transfer model which is shown to be a significant improvement compared to the existing ones.
Advisors/Committee Members: Verhelst, Sebastian, De Paepe, Michel.
Subjects/Keywords: Technology and Engineering; heat transfer; spark ignition; internal combustion engine; hydrogen; model; methane; methanol
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APA ·
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Manager
APA (6th Edition):
Demuynck, J. (2012). A fuel independent heat transfer correlation for premixed spark ignition engines. (Thesis). Ghent University. Retrieved from http://hdl.handle.net/1854/LU-3079977
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Demuynck, Joachim. “A fuel independent heat transfer correlation for premixed spark ignition engines.” 2012. Thesis, Ghent University. Accessed April 13, 2021.
http://hdl.handle.net/1854/LU-3079977.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Demuynck, Joachim. “A fuel independent heat transfer correlation for premixed spark ignition engines.” 2012. Web. 13 Apr 2021.
Vancouver:
Demuynck J. A fuel independent heat transfer correlation for premixed spark ignition engines. [Internet] [Thesis]. Ghent University; 2012. [cited 2021 Apr 13].
Available from: http://hdl.handle.net/1854/LU-3079977.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Demuynck J. A fuel independent heat transfer correlation for premixed spark ignition engines. [Thesis]. Ghent University; 2012. Available from: http://hdl.handle.net/1854/LU-3079977
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Universidade Estadual de Campinas
30.
Santos Júnior, Francisco Renato dos, 1990-.
Estudo de um modelo computacional para prever a ocorrência da detonação em um motor avançado a etanol.
Degree: Faculdade de Engenharia Mecânica; Programa de Pós-Graduação em Engenharia Mecânica, 2017, Universidade Estadual de Campinas
URL: http://repositorio.unicamp.br/jspui/handle/REPOSIP/330729
► Orientador: Janito Vaqueiro Ferreira
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica
Made available in DSpace on 2018-01-30T13:02:33Z (GMT). No. of bitstreams:…
(more)
▼ Orientador: Janito Vaqueiro Ferreira
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica
Made available in DSpace on 2018-01-30T13:02:33Z (GMT). No. of bitstreams: 1 SantosJunior_FranciscoRenatoDos_M.pdf: 4072101 bytes, checksum: 7a322b1ffbb8898c0f3603ab4b319204 (MD5) Previous issue date: 2017
Resumo: Neste presente trabalho é apresentado um método para a predição da ocorrência da detonação em um motor de ignição por centelha operando com etanol hidratado (E95h). O método é baseado na simulação de um motor, implementado em modelo fenomenologico de duas zonas. O modelo de predição considerando as variavéis pressão, temperatura e octanagem do combustível é formulado e calibrado com dados experimentais, baseado no Knock Integral Method (KIM) encontrado na literatura. Após as devidas calibrações é analisada a influência dos fatores: temperatura ambiente, temperature de parede de cilindro, umidade,
octanagem, avanço e taxa de compressão. Os resultados obtidos foram coerentes e esperados apesar de utilizar baixo custo computacional e mostraram alternativas para o controle da detonação
In this work it is presented a method for the prediction of the onset knock phenomenon on a spark ignition engine operating with hydrous ethanol (E95h). The method is based on the simulation of the engine, implemented in a two-zone non-dimensional model. A knock model considering multi-variable effects including pressure, temperature and octane number is formulated and calibrated with experimental data, based on Knock Integral Method found in literature. After the calibration, it is analysed the influence of such factors: ambient temperature, cylinder wall temperature, relative humidity, octane number and compression rate. The obtained results were coherent and expected despite low computational cost required and showed alternative ways to control knock occurrence
Mestrado
Mecanica dos
Sólidos e Projeto Mecanico
Mestre em Engenharia Mecânica
2015/24187-8
FAPESP
Advisors/Committee Members: UNIVERSIDADE ESTADUAL DE CAMPINAS, Ferreira, Janito Vaqueiro, 1961-, Gallo, Waldyr Luiz Ribeiro, Laganá, Armando Antônio Maria.
Subjects/Keywords: Detonação; Combustão; Etanol hidratado; Motores de combustão interna; Knock; Combustion; Hydrous Ethanol; Spark ignition engines
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APA ·
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APA (6th Edition):
Santos Júnior, Francisco Renato dos, 1. (2017). Estudo de um modelo computacional para prever a ocorrência da detonação em um motor avançado a etanol. (Doctoral Dissertation). Universidade Estadual de Campinas. Retrieved from http://repositorio.unicamp.br/jspui/handle/REPOSIP/330729
Chicago Manual of Style (16th Edition):
Santos Júnior, Francisco Renato dos, 1990-. “Estudo de um modelo computacional para prever a ocorrência da detonação em um motor avançado a etanol.” 2017. Doctoral Dissertation, Universidade Estadual de Campinas. Accessed April 13, 2021.
http://repositorio.unicamp.br/jspui/handle/REPOSIP/330729.
MLA Handbook (7th Edition):
Santos Júnior, Francisco Renato dos, 1990-. “Estudo de um modelo computacional para prever a ocorrência da detonação em um motor avançado a etanol.” 2017. Web. 13 Apr 2021.
Vancouver:
Santos Júnior, Francisco Renato dos 1. Estudo de um modelo computacional para prever a ocorrência da detonação em um motor avançado a etanol. [Internet] [Doctoral dissertation]. Universidade Estadual de Campinas; 2017. [cited 2021 Apr 13].
Available from: http://repositorio.unicamp.br/jspui/handle/REPOSIP/330729.
Council of Science Editors:
Santos Júnior, Francisco Renato dos 1. Estudo de um modelo computacional para prever a ocorrência da detonação em um motor avançado a etanol. [Doctoral Dissertation]. Universidade Estadual de Campinas; 2017. Available from: http://repositorio.unicamp.br/jspui/handle/REPOSIP/330729
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Open Access Theses and Dissertations
