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You searched for subject:(Ignition modes). Showing records 1 – 3 of 3 total matches.

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University of Illinois – Urbana-Champaign

1. Motily, Austen. Evaluation of hot surface ignition device performance with high-pressure kerosene fuel sprays.

Degree: MS, Mechanical Engineering, 2020, University of Illinois – Urbana-Champaign

Among the range of commercially feasible propulsion systems, compression ignition (CI) engines present many advantages for light-duty vehicle operation. In particular, CI engines remain an optimal choice for unmanned aerial vehicles (UAVs) designed to operate at moderate flight speeds. However, one of the primary limitations of CI engines is that they require well-characterized, highly-reactive diesel fuel to operate properly. As the United States Department of Defense implements the single fuel concept and with global efforts to develop alternatively derived fuels, it is paramount that modern CI engines have the capability to perform with a diverse variety of fuel types. At its core, this challenge can be framed as an ignition problem, where low reactivity fuels and extreme operating conditions result in long ignition delays, engine misfires, and power loss. It is for this reason that novel ignition devices be developed to support reliable CI engine operation. Hot surface energy addition devices are a promising technology to improve ignition behavior, but the mechanisms by which the heating element supports the ignition process are not well understood. This study evaluates the performance and limitations of commercial off-the-shelf (COTS) heating elements in functioning as continuous-use ignition devices for kerosene-fueled CI engines. Furthermore, it examines the interaction between a single high-pressure fuel spray with a hot surface device in order to identify the most important parameters for optimizing ignition behavior. Results of these experiments demonstrate that existing heating elements can accelerate the ignition process for fuels with a wide range of reactivities, assuming a sufficient surface temperature can be achieved. Reaching these temperatures in an engine environment and maintaining these temperatures for long periods of operation, with acceptable heating element durability, will be the primary challenges in developing next-generation ignition systems. Advisors/Committee Members: Lee, Tonghun (advisor).

Subjects/Keywords: Hot surface ignition; Rapid compression machine; Fuel spray ignition; Energy assisted ignition; High-pressure fuel spray; Ignition modes; Ignition device; Fuel spray heat release; Low-reactivity fuels; High-speed chemiluminescence imaging

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Motily, A. (2020). Evaluation of hot surface ignition device performance with high-pressure kerosene fuel sprays. (Thesis). University of Illinois – Urbana-Champaign. Retrieved from http://hdl.handle.net/2142/107927

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):

Motily, Austen. “Evaluation of hot surface ignition device performance with high-pressure kerosene fuel sprays.” 2020. Thesis, University of Illinois – Urbana-Champaign. Accessed January 22, 2021. http://hdl.handle.net/2142/107927.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

Motily, Austen. “Evaluation of hot surface ignition device performance with high-pressure kerosene fuel sprays.” 2020. Web. 22 Jan 2021.

Vancouver:

Motily A. Evaluation of hot surface ignition device performance with high-pressure kerosene fuel sprays. [Internet] [Thesis]. University of Illinois – Urbana-Champaign; 2020. [cited 2021 Jan 22]. Available from: http://hdl.handle.net/2142/107927.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Motily A. Evaluation of hot surface ignition device performance with high-pressure kerosene fuel sprays. [Thesis]. University of Illinois – Urbana-Champaign; 2020. Available from: http://hdl.handle.net/2142/107927

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation


University of Michigan

2. Martin, Jonathan. Exploring the Combustion Modes of A Dual-Fuel Compression Ignition Engine.

Degree: PhD, Mechanical Engineering, 2019, University of Michigan

Compression-ignition (CI) engines, also known as “diesel” engines, can produce higher thermal efficiency (TE) than spark-ignition (SI) engines, which allows them to emit less carbon dioxide (CO2) per unit of energy generated. Unfortunately, in practice the TE of CI engines is limited by the need to maintain sufficiently low emissions of nitrogen oxides (NOx) and soot. This problem can be mitigated by operating CI engines in dual-fuel modes with port fuel injection (PFI) of gasoline supplementing the direct injection (DI) of diesel fuel. Several strategies for doing this have been introduced in recent years, but these operating modes are usually studied individually at discrete conditions. This thesis introduces a classification system for dual-fuel CI modes that links together several previously studied modes across a continuous two-dimensional diagram. The combustion modes covered by this system include the standard modes of conventional diesel combustion (CDC) and conventional dual-fuel (CDF); the well-explored advanced combustion modes of HCCI, RCCI, PCCI, and PPCI; and a relatively unexplored combustion mode that is herein titled “Piston-split Dual-Fuel Combustion” or PDFC. The results show that dual-fuel CI engines can simultaneously increase TE and lower NOx and/or soot emissions at high loads through the use of Partial HCCI (PHCCI), despite an increase in emissions of carbon monoxide (CO) and unburnt hydrocarbons (UHC). At low loads, PHCCI is not possible, but either PDFC or RCCI can be used to further improve NOx and/or soot emissions, albeit at slightly lower TE and still higher emissions of CO and UHC. This multi-mode strategy of PHCCI at high loads and PDFC or RCCI at low loads is particularly useful when low engine-out NOx emissions are required. Advisors/Committee Members: Boehman, Andre L (committee member), Lastoskie, Christian M (committee member), Lavoie, George A (committee member), Middleton, Robert John (committee member), Wooldridge, Margaret S (committee member).

Subjects/Keywords: compression-ignition engines; dual-fuel combustion; advanced combustion modes; RCCI; HCCI; thermal efficiency; Mechanical Engineering; Engineering

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Martin, J. (2019). Exploring the Combustion Modes of A Dual-Fuel Compression Ignition Engine. (Doctoral Dissertation). University of Michigan. Retrieved from http://hdl.handle.net/2027.42/153383

Chicago Manual of Style (16th Edition):

Martin, Jonathan. “Exploring the Combustion Modes of A Dual-Fuel Compression Ignition Engine.” 2019. Doctoral Dissertation, University of Michigan. Accessed January 22, 2021. http://hdl.handle.net/2027.42/153383.

MLA Handbook (7th Edition):

Martin, Jonathan. “Exploring the Combustion Modes of A Dual-Fuel Compression Ignition Engine.” 2019. Web. 22 Jan 2021.

Vancouver:

Martin J. Exploring the Combustion Modes of A Dual-Fuel Compression Ignition Engine. [Internet] [Doctoral dissertation]. University of Michigan; 2019. [cited 2021 Jan 22]. Available from: http://hdl.handle.net/2027.42/153383.

Council of Science Editors:

Martin J. Exploring the Combustion Modes of A Dual-Fuel Compression Ignition Engine. [Doctoral Dissertation]. University of Michigan; 2019. Available from: http://hdl.handle.net/2027.42/153383


Universitat Politècnica de València

3. 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

[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 · Vancouver · CSE | Export to Zotero / EndNote / Reference 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 January 22, 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. 22 Jan 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 Jan 22]. 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

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