+publisher:"Penn State University" +contributor:("Daniel Connell Haworth, Dissertation Advisor/Co-Advisor")

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Penn State University

1. Bhattacharjee, Subhasish. Pdf Modeling of High-pressure Turbulent Spray Combustion under Diesel-engine-like Conditions.

Degree: 2012, Penn State University

URL: https://submit-etda.libraries.psu.edu/catalog/16057

► This thesis is focused on understanding the extent to which turbulent fluctuations in composition and temperature influence global ignition characteristics (e.g., ignition delays and liftoff… (more)

▼ This thesis is focused on understanding the extent to which turbulent fluctuations in composition and temperature influence global ignition characteristics (e.g., ignition delays and liftoff lengths) and flame structure for high-pressure, transient, autoigniting spray flames under diesel-engine-like conditions. Turbulent spray flames for two single-component fuels (n-heptane and n-dodecane) are simulated. The modeling framework is a hybrid Lagrangian-particle/Eulerian-mesh probability density function (PDF) method. This framework allows for arbitrarily large chemical mechanisms, and features Lagrangian-based spray breakup and dispersed-phase models, soot models, and an optically thin radiation model. The influence of turbulent fluctuations is explored by comparing results from the PDF method (which explicitly accounts for turbulent fluctuations) with those from a model that neglects the influence of turbulent fluctuations on local mean chemical reaction rates (a well-stirred reactor – WSR – model) for the same chemical mechanism. Computed results are compared with experimental measurements that are available through the Engine Combustion Network. Here a 40-species mechanism has been adopted for n-heptane, and a 103-species chemical mechanism for n-dodecane. Overall, it is found that for conditions that correspond to robust diesel combustion (e.g., high initial temperatures, high initial pressures and/or high oxygen concentrations) the computed liftoff lengths and ignition delays for the WSR and PDF models are close to each other, and both are in good agreement with experiments. For less robust conditions (e.g., low initial temperatures and/or low oxygen concentrations), the computed liftoff lengths and ignition delays from the two models can be significantly different, and the results from the PDF model are generally in better agreement with measurements. The differences between the two models are especially apparent for n-dodecane at low initial temperatures. For n-dodecane at an initial temperature of 800 K, the WSR model fails to ignite, while the PDF model shows a distinct two-stage autoignition process and the computed ignition delay and liftoff length are within 30% of the experimental values. For n-dodecane at an initial temperature of 900 K, the WSR model predicts an ignition delay that is three times higher than the measured value, while the PDF model prediction is within 5% of the measurement. For both fuels and for all initial conditions, the WSR and PDF models produce significantly different turbulent flame structures, and the differences are greater for lower initial temperatures and/or oxygen concentrations. The WSR model produces a laminar-like flame structure, whereas the PDF model produces a broader turbulent flame brush that is qualitatively more consistent with what is expected for a turbulent flame, and with what is observed in the experiments. While it has been shown in the literature that some global characteristics (e.g., ignition delays and liftoff lengths) of high-pressure turbulent spray… Advisors/Committee Members: Advisor%22%29&pagesize-30">Daniel Connell Haworth, Dissertation Advisor/Co-Advisor, Stephen R Turns, Committee Member, Savas Yavuzkurt, Committee Member, Andre Louis Boehman, Committee Member.

Subjects/Keywords: Turbulence; Combustion; TCI; WSR; PDF

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APA (6^th Edition):

Bhattacharjee, S. (2012). Pdf Modeling of High-pressure Turbulent Spray Combustion under Diesel-engine-like Conditions. (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/16057

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

Chicago Manual of Style (16^th Edition):

Bhattacharjee, Subhasish. “Pdf Modeling of High-pressure Turbulent Spray Combustion under Diesel-engine-like Conditions.” 2012. Thesis, Penn State University. Accessed March 06, 2021. https://submit-etda.libraries.psu.edu/catalog/16057.

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

MLA Handbook (7^th Edition):

Bhattacharjee, Subhasish. “Pdf Modeling of High-pressure Turbulent Spray Combustion under Diesel-engine-like Conditions.” 2012. Web. 06 Mar 2021.

Vancouver:

Bhattacharjee S. Pdf Modeling of High-pressure Turbulent Spray Combustion under Diesel-engine-like Conditions. [Internet] [Thesis]. Penn State University; 2012. [cited 2021 Mar 06]. Available from: https://submit-etda.libraries.psu.edu/catalog/16057.

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

Council of Science Editors:

Bhattacharjee S. Pdf Modeling of High-pressure Turbulent Spray Combustion under Diesel-engine-like Conditions. [Thesis]. Penn State University; 2012. Available from: https://submit-etda.libraries.psu.edu/catalog/16057

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

Penn State University

2. Zhao, Xinyu. Transported Probability Density Function Methods for Coal Combustion: Toward High Temperature Oxy-coal for Direct Power Extraction.

Degree: 2013, Penn State University

URL: https://submit-etda.libraries.psu.edu/catalog/19995

► A transported composition probability density function (PDF) method is developed for coal combustion, targeting high-temperature oxy-coal combustion for direct power extraction using magnetohydrodynamics. A consistent… (more)

▼ A transported composition probability density function (PDF) method is developed for coal combustion, targeting high-temperature oxy-coal combustion for direct power extraction using magnetohydrodynamics. A consistent hybrid Lagrangian particle/Eulerian mesh algorithm is used to solve the modeled PDF transport equation for the gas phase, with finite-rate gas-phase chemistry. The model includes standard k-epsilon turbulence, gradient transport for scalars, and a Euclidean minimum spanning tree (EMST) mixing model. A separate Lagrangian description is used to solve for the coal particle phase, including particle tracking, devolatilization and surface reaction models. Inter-phase coupling models are proposed for the couplings between the gas phase and the solid phase. A spectral photon Monte Carlo (PMC) method is built into the framework to account for the spectral radiative heat transfer for the gas phase. A systematic hierarchical approach has been pursued for model development. First, simulations were performed for laboratory-scale syngas (CO/H2/N2)-air jet flames where finite-rate chemistry is important. The next step was to simulate an oxy-natural gas furnace where the environment is as close as possible to that in an oxy-coal system, without the complications of a solid fuel. The model was then extended to include coal particles, and was tested both for a nonreacting particle-laden expansion flow and for two reacting air-coal jet flames. It has been found that turbulence-chemistry interactions are important in all the validation cases when species with slow chemistry are considered (e.g., CO, NO). Radiation dominates the heat-transfer characteristics in a high-temperature oxy-combustion environment, although the effects of turbulence-radiation interactions might not be significant. For coal combustion, finite-rate chemistry is important for correct flame structure predictions. The high-fidelity models constructed here have proven to be robust in different combustion environments, and have been exercised to calibrate simpler models and to test model assumptions that often are included in simpler models. Advisors/Committee Members: Advisor%22%29&pagesize-30">Daniel Connell Haworth, Dissertation Advisor/Co-Advisor, Stephen R Turns, Committee Member, Philip John Morris, Committee Member, Sarma V Pisupati, Committee Member.

Subjects/Keywords: oxy-coal combustion; combustion modeling; probability density function method; spectral photon Monte Carlo; finite-rate chemistry

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APA (6^th Edition):

Zhao, X. (2013). Transported Probability Density Function Methods for Coal Combustion: Toward High Temperature Oxy-coal for Direct Power Extraction. (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/19995

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

Chicago Manual of Style (16^th Edition):

Zhao, Xinyu. “Transported Probability Density Function Methods for Coal Combustion: Toward High Temperature Oxy-coal for Direct Power Extraction.” 2013. Thesis, Penn State University. Accessed March 06, 2021. https://submit-etda.libraries.psu.edu/catalog/19995.

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

MLA Handbook (7^th Edition):

Zhao, Xinyu. “Transported Probability Density Function Methods for Coal Combustion: Toward High Temperature Oxy-coal for Direct Power Extraction.” 2013. Web. 06 Mar 2021.

Vancouver:

Zhao X. Transported Probability Density Function Methods for Coal Combustion: Toward High Temperature Oxy-coal for Direct Power Extraction. [Internet] [Thesis]. Penn State University; 2013. [cited 2021 Mar 06]. Available from: https://submit-etda.libraries.psu.edu/catalog/19995.

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

Council of Science Editors:

Zhao X. Transported Probability Density Function Methods for Coal Combustion: Toward High Temperature Oxy-coal for Direct Power Extraction. [Thesis]. Penn State University; 2013. Available from: https://submit-etda.libraries.psu.edu/catalog/19995

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

Penn State University

3. Raj Mohan, Vivek Raja. Development and application of a transported probability density function model for advanced compression-ignition engines.

Degree: 2014, Penn State University

URL: https://submit-etda.libraries.psu.edu/catalog/22944

► A transported probability density function (PDF) method is coupled with a deforming/moving grid with periodic removal/addition of layers of cells to accommodate piston motion in… (more)

▼ A transported probability density function (PDF) method is coupled with a deforming/moving grid with periodic removal/addition of layers of cells to accommodate piston motion in engine modeling. The coupled model is used to simulate in-cylinder combustion processes for heavy-duty compression-ignition engines. First, the influences of unresolved turbulent fluctuations in composition and temperature (turbulence-chemistry interactions – TCI) on heat release, flame structure, and emissions are explored at four operating conditions in a conventional diesel engine. TCI are isolated and quantified by comparing results from the transported PDF model with those from a model that neglects the influence of fluctuations on local mean reaction rates (a well-stirred-reactor – WSR-model), with all other aspects of the modeling being the same (e.g., spray model, gas-phase chemical mechanism, and soot model). Computed pressure and heat-release traces, turbulent flame structure, and emissions from the WSR and PDF models show marked differences, with the PDF-model results being in closer agreement with experiment in most cases. While the peak cylinder pressure values predicted by the PDF model are within 3% of the measured data, those predicted by the WSR model differ up to 10.5% from experimental data. The soot results are especially striking. Computed soot levels from the PDF model are within a factor of five of the measured engine-out particulate matter, and computed soot levels from the WSR and PDF models differ by up to several orders of magnitude, with the PDF-model results being in much closer agreement with experiment. These results highlight the importance of TCI in compression-ignition engines. Second, one of the advanced combustion modes – partially premixed combustion – is studied using gasoline as fuel. It is observed that at least four components are required to form a gasoline surrogate to predict the ignition characteristics, flame structure and emissions accurately. A good surrogate chemical mechanism needs to be validated for two-component primary reference fuel (PRF) mixtures (mixtures of n-heptane and iso-octane) and three-component toluene reference fuel mixtures (mixtures of n-heptane, iso-octane and toluene) under heavy-duty engine conditions before using it to predict gasoline combustion characteristics. Several PRF chemical mechanisms are tested to model the combustion of two-component PRF mixtures, and none of them satisfactorily match the experimental data. Those mechanisms that have been primarily developed to study leaner combustion conditions predict a longer ignition delay compared to experiments. Finally, a new combustion concept based on advanced combustion strategies has been explored. A preliminary study of this concept shows tremendous potential to increase efficiency. Advisors/Committee Members: Advisor%22%29&pagesize-30">Daniel Connell Haworth, Dissertation Advisor/Co-Advisor, Daniel Connell Haworth, Committee Chair/Co-Chair, Andre Louis Boehman, Committee Member, Stephen R Turns, Committee Member, Savas Yavuzkurt, Committee Member.

Subjects/Keywords: PDF model; compression-ignition engines; engine modeling; soot modeling; gasoline engine; heavy-duty engines; CFD modeling

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APA (6^th Edition):

Raj Mohan, V. R. (2014). Development and application of a transported probability density function model for advanced compression-ignition engines. (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/22944

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

Chicago Manual of Style (16^th Edition):

Raj Mohan, Vivek Raja. “Development and application of a transported probability density function model for advanced compression-ignition engines.” 2014. Thesis, Penn State University. Accessed March 06, 2021. https://submit-etda.libraries.psu.edu/catalog/22944.

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

MLA Handbook (7^th Edition):

Raj Mohan, Vivek Raja. “Development and application of a transported probability density function model for advanced compression-ignition engines.” 2014. Web. 06 Mar 2021.

Vancouver:

Raj Mohan VR. Development and application of a transported probability density function model for advanced compression-ignition engines. [Internet] [Thesis]. Penn State University; 2014. [cited 2021 Mar 06]. Available from: https://submit-etda.libraries.psu.edu/catalog/22944.

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

Council of Science Editors:

Raj Mohan VR. Development and application of a transported probability density function model for advanced compression-ignition engines. [Thesis]. Penn State University; 2014. Available from: https://submit-etda.libraries.psu.edu/catalog/22944

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

Penn State University

4. Zhang, Hedan. Effects of turbulence-chemistry interactions in direct-injection compression-ignition engines.

Degree: 2012, Penn State University

URL: https://submit-etda.libraries.psu.edu/catalog/16172

► Advanced combustion strategies are emphasized in modern compression-ignition engine systems, aiming at improving diesel engine efficiency and reducing pollutant emissions, especially soot and NOx, together… (more)

▼ Advanced combustion strategies are emphasized in modern compression-ignition engine systems, aiming at improving diesel engine efficiency and reducing pollutant emissions, especially soot and NOx, together with strategies to accommodate unconventional fuels. Recent studies have shown the importance of turbulence and turbulence-chemistry interactions on emissions from laboratory flames and compression-ignition engines. Constant-volume, high-pressure spray combustion is an important intermediate step for model validation and scientific understanding of combustion in direct-injection compression-ignition engines. The Engine Combustion Network (ECN) provides a series of well-documented experimental data for spray combustion under typical diesel-engine conditions, and this serves as a good resource for simulation and validation purposes. Here simulations for the ECN constant-volume, n-heptane spray configuration have been performed using OpenFOAM, an object-oriented C++ based code. The effects of exhaust-gas recirculation (EGR), ambient temperature and density on combustion were investigated computationally. The simulations demonstrate that the CFD model is capable of predicting sprays, mixing, ignition and combustion, quantitatively, for engine-relevant conditions reasonably well. The numerical results show that the ignition delay and lift-off lengths are strongly influenced by EGR, ambient gas temperature and ambient gas density, in agreement with measurements. Results from a model using a transported probability density function (PDF) method that explicitly accounts for turbulence-chemistry interactions have been compared to those from a model that simplistically accounts for turbulence-chemistry interactions, including mixture fraction profiles, ignition delays, lift-off lengths and flame structures under various ambient conditions. Significant differences between these two models have been observed, whichshows the importance of turbulence-chemistry interactions. The turbulent flame structure predicted by the PDF method is more realistic than that obtained from a simplistic model to account for turbulence-chemistry interactions. The choice of chemical mechanism also plays a strong role. Next, the high-fidelity CFD-based models have been used to simulate fuel effects and complex interactions between turbulence and gas-phase chemistry on emissions for biodiesel combustion and hydrogen-assisted diesel combustion in common-rail diesel engines. The sensitivity of predicted NOx emissions to variations in the physical properties of the fuel (density and viscosity) has been explored to determine the origins of the so-called biodiesel-NOx effect: the increase in NOx emissions that has been observed when petroleum-based diesel fuel is replaced with biodiesel fuel. Interactions between turbulence and gas-phase chemistry have been found to be important in the fuel density effect on NOx emissions. CFD also has been used to explore the changes in NOx emissions with hydrogen substitution that have been observed experimentally in… Advisors/Committee Members: Advisor%22%29&pagesize-30">Daniel Connell Haworth, Dissertation Advisor/Co-Advisor, Daniel Connell Haworth, Committee Chair/Co-Chair, Stephen R Turns, Committee Member, James Gordon Brasseur, Committee Member, Andre Louis Boehman, Committee Member.

Subjects/Keywords: turbulence-chemistry interactions; probability density function; diesel engine; NOx; n-heptane

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

APA (6^th Edition):

Zhang, H. (2012). Effects of turbulence-chemistry interactions in direct-injection compression-ignition engines. (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/16172

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

Chicago Manual of Style (16^th Edition):

Zhang, Hedan. “Effects of turbulence-chemistry interactions in direct-injection compression-ignition engines.” 2012. Thesis, Penn State University. Accessed March 06, 2021. https://submit-etda.libraries.psu.edu/catalog/16172.

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

MLA Handbook (7^th Edition):

Zhang, Hedan. “Effects of turbulence-chemistry interactions in direct-injection compression-ignition engines.” 2012. Web. 06 Mar 2021.

Vancouver:

Zhang H. Effects of turbulence-chemistry interactions in direct-injection compression-ignition engines. [Internet] [Thesis]. Penn State University; 2012. [cited 2021 Mar 06]. Available from: https://submit-etda.libraries.psu.edu/catalog/16172.

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

Council of Science Editors:

Zhang H. Effects of turbulence-chemistry interactions in direct-injection compression-ignition engines. [Thesis]. Penn State University; 2012. Available from: https://submit-etda.libraries.psu.edu/catalog/16172

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

Penn State University

5. Shekhawat, Yajuvendra Singh. Large-Eddy Simulations of Motored Flow and Combustion in a Homogeneous-Charge Spark-Ignition Engine.

Degree: 2017, Penn State University

URL: https://submit-etda.libraries.psu.edu/catalog/13827yss107

► Cycle-to-cycle variations (CCV) of flow and combustion in internal combustion engines (ICE) limit their fuel efficiency and emissions potential. Large-eddy simulation (LES) is the most… (more)

▼ Cycle-to-cycle variations (CCV) of flow and combustion in internal combustion engines (ICE) limit their fuel efficiency and emissions potential. Large-eddy simulation (LES) is the most practical simulation tool to understand the nature of these CCV. In this research, multi-cycle LES of a two-valve, four-stroke, spark- ignition optical engine has been performed for motored and fired operations. The LES mesh quality is assessed using a length scale resolution parameter and a energy resolution parameter. For the motored operation, two 50-consecutive-cycle LES with different turbulence models (Smagorinsky model and dynamic structure model) are compared with the experiment. The pressure comparison shows that the LES is able to capture the wave-dynamics in the intake and exhaust ports. The LES velocity fields are compared with particle-image velocimetry (PIV) measurements at three cutting planes. Based on the structure and magnitude indices, the dynamic structure model is somewhat better than the Smagorinsky model as far as the ensemble-averaged velocity fields are concerned. The CCV in the velocity fields is assessed by proper-orthogonal decomposition (POD). The POD analysis shows that LES is able to capture the level of CCV seen in the experiment. For the fired operation, two 60-cycle LES with different combustion models (thickened flame model and coherent flame model) are compared with experiment. The in-cylinder pressure and the apparent heat release rate comparison shows higher CCV for LES compared to the experiment, with the thickened flame model showing higher CCV than the coherent flame model. The correlation analysis for the LES using thickened flame model shows that the CCV in combustion/pressure is correlated with: the tumble at the intake valve closing, the resolved and subfilter-scale kinetic energy just before spark time, and the second POD mode (shear flow near spark gap) of the velocity fields just before spark time. Advisors/Committee Members: Advisor%22%29&pagesize-30">Daniel Connell Haworth, Dissertation Advisor/Co-Advisor, Daniel Connell Haworth, Committee Chair/Co-Chair, Stephen Turns, Committee Member, Robert Santoro, Committee Member, Philip John Morris, Outside Member.

Subjects/Keywords: Spark-ignition engines; Cycle-to-cycle variations; Large-eddy simulations; Thickened flame model

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APA (6^th Edition):

Shekhawat, Y. S. (2017). Large-Eddy Simulations of Motored Flow and Combustion in a Homogeneous-Charge Spark-Ignition Engine. (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/13827yss107

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

Chicago Manual of Style (16^th Edition):

Shekhawat, Yajuvendra Singh. “Large-Eddy Simulations of Motored Flow and Combustion in a Homogeneous-Charge Spark-Ignition Engine.” 2017. Thesis, Penn State University. Accessed March 06, 2021. https://submit-etda.libraries.psu.edu/catalog/13827yss107.

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

MLA Handbook (7^th Edition):

Shekhawat, Yajuvendra Singh. “Large-Eddy Simulations of Motored Flow and Combustion in a Homogeneous-Charge Spark-Ignition Engine.” 2017. Web. 06 Mar 2021.

Vancouver:

Shekhawat YS. Large-Eddy Simulations of Motored Flow and Combustion in a Homogeneous-Charge Spark-Ignition Engine. [Internet] [Thesis]. Penn State University; 2017. [cited 2021 Mar 06]. Available from: https://submit-etda.libraries.psu.edu/catalog/13827yss107.

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

Council of Science Editors:

Shekhawat YS. Large-Eddy Simulations of Motored Flow and Combustion in a Homogeneous-Charge Spark-Ignition Engine. [Thesis]. Penn State University; 2017. Available from: https://submit-etda.libraries.psu.edu/catalog/13827yss107

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

Penn State University

6. Jaishree, Jaishree. LAGRANGIAN AND EULERIAN PROBABILITY DENSITY FUNCTION METHODS FOR TURBULENT REACTING FLOWS.

Degree: 2011, Penn State University

URL: https://submit-etda.libraries.psu.edu/catalog/12549

► Transported probability density function (PDF) methods have been applied widely and effectively for modeling turbulent reacting flows. In most applications of PDF methods to date,… (more)

▼ Transported probability density function (PDF) methods have been applied widely and effectively for modeling turbulent reacting flows. In most applications of PDF methods to date, Lagrangian particle Monte Carlo algorithms have been used to solve a modeled PDF transport equation. However, Lagrangian particle PDF methods are computationally expensive and are not readily integrated into conventional Eulerian CFD codes. Eulerian field PDF methods have been proposed as an alternative. Here a systematic comparison is performed among three methods for solving the same underlying modeled composition PDF transport equation: a consistent hybrid Lagrangian particle/Eulerian mesh (LPEM) method, a stochastic Eulerian field (SEF) method, and a deterministic Eulerian field method with a direct-quadrature-method-of-moments closure (a multi-environment PDF - MEPDF - method). The comparisons have been made in simulations of a series of three nonpremixed, piloted methane-air turbulent jet flames that exhibit progressively increasing levels of local extinction and turbulence-chemistry interactions: Sandia/Technische Universit¨at Darmstadt (TUD) flames D, E and F. The three PDF methods have been implemented using the same underlying CFD solver, and results obtained using the three methods have been compared using (to the extent possible) equivalent physical models and numerical parameters. Reasonably converged mean and rms scalar profiles are obtained using 40 particles per cell for the LPEM method or 40 Eulerian fields for the SEF method. Results from these stochastic methods are compared with results obtained using two- and three-environment MEPDF methods. The relative advantages and disadvantages of each method in terms of accuracy and computational requirements are explored and identified. In general, the results obtained from the two stochastic methods (LPEM and SEF) are very similar, and are in closer agreement with experimental measurements than those obtained using the MEPDF method, while MEPDF is the most computationally efficient of the three methods. The advantages of Eulerian PDF methods over Lagrangian PDF methods are expected to be especially compelling for complex configurations with deforming computational meshes: e.g., in-cylinder flows in reciprocating-piston internal combustion engines. As a first step in that direction, a SEF PDF method has been coupled with a fuel spray model and a soot model, and initial simulations have been performed for constant-volume turbulent spray combustion under diesel-engine-like conditions. Differences in results of simulations with versus without the SEF PDF method suggest that consideration of turbulence-chemistry interactions is of prime importance. These and other findings are discussed in detail. Advisors/Committee Members: Advisor%22%29&pagesize-30">Daniel Connell Haworth, Dissertation Advisor/Co-Advisor, Daniel Connell Haworth, Committee Chair/Co-Chair, Gita Talmage, Committee Member, Padma Raghavan, Committee Member, Stephen R Turns, Committee Member.

Subjects/Keywords: Nonpremixed turbulent flames; Probability density

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

APA (6^th Edition):

Jaishree, J. (2011). LAGRANGIAN AND EULERIAN PROBABILITY DENSITY FUNCTION METHODS FOR TURBULENT REACTING FLOWS. (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/12549

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

Chicago Manual of Style (16^th Edition):

Jaishree, Jaishree. “LAGRANGIAN AND EULERIAN PROBABILITY DENSITY FUNCTION METHODS FOR TURBULENT REACTING FLOWS.” 2011. Thesis, Penn State University. Accessed March 06, 2021. https://submit-etda.libraries.psu.edu/catalog/12549.

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

MLA Handbook (7^th Edition):

Jaishree, Jaishree. “LAGRANGIAN AND EULERIAN PROBABILITY DENSITY FUNCTION METHODS FOR TURBULENT REACTING FLOWS.” 2011. Web. 06 Mar 2021.

Vancouver:

Jaishree J. LAGRANGIAN AND EULERIAN PROBABILITY DENSITY FUNCTION METHODS FOR TURBULENT REACTING FLOWS. [Internet] [Thesis]. Penn State University; 2011. [cited 2021 Mar 06]. Available from: https://submit-etda.libraries.psu.edu/catalog/12549.

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

Council of Science Editors:

Jaishree J. LAGRANGIAN AND EULERIAN PROBABILITY DENSITY FUNCTION METHODS FOR TURBULENT REACTING FLOWS. [Thesis]. Penn State University; 2011. Available from: https://submit-etda.libraries.psu.edu/catalog/12549

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

Penn State University

7. Dasgupta, Adhiraj Kishore. Numerical Simulation of AxiSymmetric Laminar Diffusion Flames with Soot.

Degree: 2015, Penn State University

URL: https://submit-etda.libraries.psu.edu/catalog/27357

► Detailed numerical modeling of combustion phenomena, soot formation, and radi- ation is an active area of research. In this work a general-purpose, pressure-based, finite volume… (more)

▼ Detailed numerical modeling of combustion phenomena, soot formation, and radi- ation is an active area of research. In this work a general-purpose, pressure-based, finite volume code for modeling laminar diffusion flames has been incorporated into the CFD code OpenFOAM. The code uses a mixture-averaged model for the calculation of transport coefficients, and can be used to perform detailed modeling of multi-dimensional laminar flames using realistic molecular transport, and with detailed chemical mechanisms containing hundreds of chemical species and reac- tions. Two soot models have been incorporated into the code: a semi-empirical two-equation model, as well as a detailed Method of Moments with Interpolative Closure (MOMIC). An emission-only, optically-thin radiation model has also been included in the code to account for the radiative heat loss, and sophisticated radia- tion models with detailed calculations of spectral properties and radiative intensity have also been included. The flame code showed excellent scalability on massively distributed, high-performance computer systems. The code has been validated by modeling four axisymmetric, co-flowing laminar diffusion flames, and the results have been found to be mostly within experimental uncertainty, and comparable to results reported in the literature for the same and similar configurations. A number of parametric studies to study the effects of detailed gas-phase chemistry, soot models and radiation have also been performed on these flame configurations. It has been found that the flames considered in this work are all optically thin, and so the simple, emission-only, optically-thin radiation model can be used to model these flames with good accuracy and a reasonable computational effort. In particular, the detailed radiation models increase the computational cost by two orders of magnitude, and thus their applicability in a detailed calculation may be limited. It was found that the two-equation soot model used in conjunction with a gas- phase mechanism that adequately describes the combustion of C2 hydrocarbons produces results in close agreement with experimental data for a 1-bar ethylene-air flame, a 10 bar methane-air flame, as well as an ethane-air flame at 10 bar. The detailed MOMIC soot model requires the use of a larger, more detailed gas-phase chemical mechanism containing polycyclic aromatic hydrocarbons (PAH) with four rings, and thus the computational cost associated with the MOMIC soot model is significantly higher. The detailed model was used to model the flames, and computed soot levels were within a factor of two of the experimental values, which is typically considered good agreement considering the complex physics involved. The last flame studied using both the soot models was a N2 -diluted ethylene-air flame, in which the predicted values of major gas-phase species were seen to be close to the experimental values, but the soot levels were off by an order of magnitude. Notwithstanding the lack of agreement with measurements for this flame,… Advisors/Committee Members: Advisor%22%29&pagesize-30">Daniel Connell Haworth, Dissertation Advisor/Co-Advisor, Daniel Connell Haworth, Committee Chair/Co-Chair, Stephen R Turns, Committee Member, Robert John Santoro, Committee Member, Philip John Morris, Special Member.

Subjects/Keywords: soot; laminar flames; OpenFOAM; diffusion flames; CFD modeling

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APA (6^th Edition):

Dasgupta, A. K. (2015). Numerical Simulation of AxiSymmetric Laminar Diffusion Flames with Soot. (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/27357

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

Chicago Manual of Style (16^th Edition):

Dasgupta, Adhiraj Kishore. “Numerical Simulation of AxiSymmetric Laminar Diffusion Flames with Soot.” 2015. Thesis, Penn State University. Accessed March 06, 2021. https://submit-etda.libraries.psu.edu/catalog/27357.

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

MLA Handbook (7^th Edition):

Dasgupta, Adhiraj Kishore. “Numerical Simulation of AxiSymmetric Laminar Diffusion Flames with Soot.” 2015. Web. 06 Mar 2021.

Vancouver:

Dasgupta AK. Numerical Simulation of AxiSymmetric Laminar Diffusion Flames with Soot. [Internet] [Thesis]. Penn State University; 2015. [cited 2021 Mar 06]. Available from: https://submit-etda.libraries.psu.edu/catalog/27357.

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

Council of Science Editors:

Dasgupta AK. Numerical Simulation of AxiSymmetric Laminar Diffusion Flames with Soot. [Thesis]. Penn State University; 2015. Available from: https://submit-etda.libraries.psu.edu/catalog/27357

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

Penn State University

8. Liu, Kai. Large-Eddy Simulation of in-cylinder flows in motored reciprocating-piston internal combustion engines.

Degree: 2012, Penn State University

URL: https://submit-etda.libraries.psu.edu/catalog/15825

► Two key bottlenecks prevent engines from reaching their performance, efficiency, and emissions potential. The first bottleneck is limited understanding of turbulence hydrodynamics for in-cylinder flows… (more)

▼ Two key bottlenecks prevent engines from reaching their performance, efficiency, and emissions potential. The first bottleneck is limited understanding of turbulence hydrodynamics for in-cylinder flows including cycle-to-cycle variations (CCV), and the second one is the absence of an objective approach for making quantitative comparisons between simulation and experiment, beyond ensemble averaging. In this thesis, the CCV phenomenon in IC engines and its effects on IC-engine performance are introduced. Previous studies of CCV, its root causes, and its influences on engine performance are reviewed. The limitations of current practices for IC engine simulation and analysis are discussed. Large-eddy simulation (LES) has shown promise in internal combustion (IC) engine applications, and proper orthogonal decomposition (POD) has been proposed as an objective way to analyze complex turbulent flows and to make comprehensive comparisons between simulation and measurements. In the research performed here, LES and POD have been performed for two simplified motored IC engines: the Imperial College piston-cylinder assembly with and without swirl and the Transparent Combustion Chamber (TCC) engine. For the first configuration, the sensitivity of LES to key numerical and physical model parameters has been investigated. Results are especially sensitive to mesh and to the subfilter-scale (SFS) turbulence models. Satisfactory results can be obtained using simple viscosity-based SFS turbulence models, although there is room for improvement. No single model gives uniformly best agreement between model and measurements at all spatial locations and at all times. Compared to Reynolds-averaged Navier-Stokes (RANS) modeling, LES shows advantages in accuracy and in capturing more details of the complex in-cylinder flow dynamics. In particular, LES is able to capture CCV using computational meshes that are comparable to those that are used for RANS, in that case, the high computational cost of LES is mainly due to the need to compute multiple engine cycles. POD is then used to study the dynamics of the in-cylinder turbulent flow. Systematic parametric studies are performed, including two-dimensional (2-D) POD versus three-dimensional (3-D) POD, phase-dependent POD versus phase-invariant POD, and sensitivities of POD mode structure and mode convergence rate to spatial and temporal resolution. The use of POD to identify and quantify CCV is explored, and the ability of POD to distinguish between organized and disorganized flows is demonstrated. The LES and POD experience from the piston-cylinder assembly is then extended to a more realistic engine configuration (TCC engine) with full four-stroke motored cycles, where detailed particle image velocimetry (PIV) measurements are being made. The complex in-cylinder flows, including characterization of CCV, are analyzed by using LES and POD. Initial quantitative comparisons with PIV measurements are also performed. It is found that many of the key conclusions that were drawn from the POD analysis of… Advisors/Committee Members: Advisor%22%29&pagesize-30">Daniel Connell Haworth, Dissertation Advisor/Co-Advisor, Daniel Connell Haworth, Committee Chair/Co-Chair, Andre Louis Boehman, Committee Member, James Gordon Brasseur, Committee Member, Stephen R Turns, Committee Member.

Subjects/Keywords: Turbulence; � Large-eddy simulation; � Internal Combustion engine; Proper orthogonal decomposition; � Cycle-to-cycle variations

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

APA (6^th Edition):

Liu, K. (2012). Large-Eddy Simulation of in-cylinder flows in motored reciprocating-piston internal combustion engines. (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/15825

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

Chicago Manual of Style (16^th Edition):

Liu, Kai. “Large-Eddy Simulation of in-cylinder flows in motored reciprocating-piston internal combustion engines.” 2012. Thesis, Penn State University. Accessed March 06, 2021. https://submit-etda.libraries.psu.edu/catalog/15825.

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

MLA Handbook (7^th Edition):

Liu, Kai. “Large-Eddy Simulation of in-cylinder flows in motored reciprocating-piston internal combustion engines.” 2012. Web. 06 Mar 2021.

Vancouver:

Liu K. Large-Eddy Simulation of in-cylinder flows in motored reciprocating-piston internal combustion engines. [Internet] [Thesis]. Penn State University; 2012. [cited 2021 Mar 06]. Available from: https://submit-etda.libraries.psu.edu/catalog/15825.

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

Council of Science Editors:

Liu K. Large-Eddy Simulation of in-cylinder flows in motored reciprocating-piston internal combustion engines. [Thesis]. Penn State University; 2012. Available from: https://submit-etda.libraries.psu.edu/catalog/15825

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

Penn State University

9. Roy, Somesh Prasad. Aerosol-dynamics-based soot modeling of flames.

Degree: 2014, Penn State University

URL: https://submit-etda.libraries.psu.edu/catalog/20625

► Modeling of soot formation and destruction in combustion systems involves modeling of fluid dynamics, chemistry, and radiative transfer. Each of these sub-problems are highly complex… (more)

▼ Modeling of soot formation and destruction in combustion systems involves modeling of fluid dynamics, chemistry, and radiative transfer. Each of these sub-problems are highly complex in nature and computationally very intensive. Considering complexity of these inter-connected processes of real-world combustion systems and computational cost associated with their modeling, a systematic comparative study of soot models is needed to identify an affordable, yet comprehensive and accurate model of soot prediction in device-scale and real-world combustion systems. Such a systematic study of two detailed soot models is performed in the current work. The models used in this study are a discrete sectional method (DSM) and a method of moments with interpolative closure (MOMIC). A semi-empirical soot model is also included in the study for comparison. Several gas-phase chemical mechanism were also tested with the soot models to identify the relative importance of gas-phase chemical mechanisms in the outcome of the soot simulations. Results showed the importance of the surface growth and nucleation schemes in predicting the soot volume fraction. Even though the surface growth contributed most to the soot mass growth, nucleation plays a critical role in final soot volume fraction by way of influencing the soot number density. Therefore, accurate prediction of nucleating species is key to the success of detailed soot model. The comparison of DSM and MOMIC showed very similar prediction trend in global quantities. The semi-empirical model, with proper tuning, was found to perform well in all the flames studied. DSM was found computationally most costly, while the semi-empirical model was computationally least expensive. The study in laminar flames was complemented by a direct numerical simulation (DNS) of a two-dimensional turbulent flame using MOMIC. A robust numerical scheme was developed and tested for MOMIC in DNS. The effects of turbulence on gas-phase chemistry and soot dynamics were explored from the data generated. Relative importance of soot surface reactions were found to be affected by both the scalar dissipation rate and the curvature of the instantaneous flame surface. Advisors/Committee Members: Advisor%22%29&pagesize-30">Daniel Connell Haworth, Dissertation Advisor/Co-Advisor, Daniel Connell Haworth, Committee Chair/Co-Chair, Stephen R Turns, Committee Member, Robert John Santoro, Committee Member, Padma Raghavan, Committee Member.

Subjects/Keywords: soot modeling; discrete sectional model; method of moments; aerosol dynamics; laminar flame; direct numerical simulation

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

APA (6^th Edition):

Roy, S. P. (2014). Aerosol-dynamics-based soot modeling of flames. (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/20625

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

Chicago Manual of Style (16^th Edition):

Roy, Somesh Prasad. “Aerosol-dynamics-based soot modeling of flames.” 2014. Thesis, Penn State University. Accessed March 06, 2021. https://submit-etda.libraries.psu.edu/catalog/20625.

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

MLA Handbook (7^th Edition):

Roy, Somesh Prasad. “Aerosol-dynamics-based soot modeling of flames.” 2014. Web. 06 Mar 2021.

Vancouver:

Roy SP. Aerosol-dynamics-based soot modeling of flames. [Internet] [Thesis]. Penn State University; 2014. [cited 2021 Mar 06]. Available from: https://submit-etda.libraries.psu.edu/catalog/20625.

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

Council of Science Editors:

Roy SP. Aerosol-dynamics-based soot modeling of flames. [Thesis]. Penn State University; 2014. Available from: https://submit-etda.libraries.psu.edu/catalog/20625

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

Penn State University

10. Gupta, Ankur. Large-Eddy Simulation of Turbulent Flames with Radiation Heat Transfer .

Degree: 2011, Penn State University

URL: https://submit-etda.libraries.psu.edu/catalog/12300

► Most practical combustion devices involve turbulent flow and operate at high temperatures. Reliable predictive models for these devices must not only represent each individual physical… (more)

▼ Most practical combustion devices involve turbulent flow and operate at high temperatures. Reliable predictive models for these devices must not only represent each individual physical process (combustion, turbulence and radiation) with high accuracy, but also must capture the highly nonlinear interactions among these processes. In this work, a comprehensive computational tool is developed for numerical modeling of turbulent combustion systems with accurate representation of turbulence, chemistry, turbulence-chemistry interaction (TCI), radiation, and turbulence-radiation interaction (TRI). A hybrid finite-volume (FV)/particle-Monte-Carlo procedure is employed wherein a compressible FV Large-Eddy simulation (LES) formulation with a composition filtered-density function (FDF) method is used to model turbulence-chemistry interactions (TCI) and emission TRI. Nongray radiation and absorption TRI is modeled through a photon Monte Carlo (PMC) method where stochastic schemes are developed for treating thermal radiation in a turbulent flow field characterized by the notional particles of the Lagrangian-FDF method. LES/FDF/PMC computations are computationally highly expensive, and a novel "computational time-map"-based domain-decomposition technique is implemented in this study for effective parallelization of the computational code. A nonpremixed methane/air flame is simulated to demonstrate the accuracy of the code developed here. Since LES is inherently time-dependent, the PMC solution at each time step needs to be reasonably reflective of the instantaneous fields to preserve the transient nature of LES, which might require considering large number of photon bundles. Investigations are made in this work for a wide range of flames to estimate the statistical uncertainties in the PMC solution for various number of photon bundles for an instantaneous LES/FDF snapshot. The time-averaged solution is also compared for different bundle sizes. The effect of thermal radiation appears as a source term in the energy equation, which consists of filtered emission and filtered absorption terms in the LES context. In LES, since only large scales are explicitly resolved, the contribution of subfilter-scale (SFS) fluctuations to filtered emission and absorption terms (referred to as SFS emission TRI and SFS absorption TRI, respectively) need to be modeled. The importance of SFS TRI is assessed here for a wide range of flames. A state-of-the-art, advanced LES-based numerical tool for comprehensive modeling of turbulent reacting flows, encompassing all key processes in detail, has become available for the first time as a result of this work. An effective parallelization scheme is implemented in the code that scales well irrespective of the computational cost for chemistry calculations. Stochastic PMC schemes are devised that are consistent with the notional particle representation of the FDF method. It is estimated that approximately three-to-four photon bundles per grid-cell are sufficient to ensure accurate time-averaged solutions for a… Advisors/Committee Members: Advisor%22%29&pagesize-30">Daniel Connell Haworth, Dissertation Advisor/Co-Advisor, Daniel Connell Haworth, Committee Chair/Co-Chair, Michael F Modest, Committee Chair/Co-Chair, Stephen R Turns, Committee Member, Philip John Morris, Committee Member.

Subjects/Keywords: Filtered-density function; Photon Monte Carlo; Turbulence-radiation interaction; Large-eddy simulation; Combustion; Thermal radiation; Turbulence-chemistry interaction; Probability density function

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

APA (6^th Edition):

Gupta, A. (2011). Large-Eddy Simulation of Turbulent Flames with Radiation Heat Transfer . (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/12300

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

Chicago Manual of Style (16^th Edition):

Gupta, Ankur. “Large-Eddy Simulation of Turbulent Flames with Radiation Heat Transfer .” 2011. Thesis, Penn State University. Accessed March 06, 2021. https://submit-etda.libraries.psu.edu/catalog/12300.

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

MLA Handbook (7^th Edition):

Gupta, Ankur. “Large-Eddy Simulation of Turbulent Flames with Radiation Heat Transfer .” 2011. Web. 06 Mar 2021.

Vancouver:

Gupta A. Large-Eddy Simulation of Turbulent Flames with Radiation Heat Transfer . [Internet] [Thesis]. Penn State University; 2011. [cited 2021 Mar 06]. Available from: https://submit-etda.libraries.psu.edu/catalog/12300.

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

Council of Science Editors:

Gupta A. Large-Eddy Simulation of Turbulent Flames with Radiation Heat Transfer . [Thesis]. Penn State University; 2011. Available from: https://submit-etda.libraries.psu.edu/catalog/12300

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

Penn State University

11. Kazmouz, Samuel. Large-Eddy Simulations of Motored Flow and Combustion in a Stratified-Charge Direct-Injection Spark-Ignition Engine.

Degree: 2020, Penn State University

URL: https://submit-etda.libraries.psu.edu/catalog/17568xuk13

► Stratified-charge, spray-guided, spark-ignition, direct-injection operation offers efficiency improvements to conventional engines used in light-duty vehicles. However, cycle-to-cycle variability (CCV) impedes extracting the full efficiency potential… (more)

▼ Stratified-charge, spray-guided, spark-ignition, direct-injection operation offers efficiency improvements to conventional engines used in light-duty vehicles. However, cycle-to-cycle variability (CCV) impedes extracting the full efficiency potential of such advanced engine operation modes. In this dissertation, multi-cycle motored and fired large-eddy simulation (LES) results of an optically-accessible single-cylinder four-valve direct-injection spark- ignition engine, called G4VDI, are presented and compared to experimental results. The main objective is to investigate the root causes of CCV in stratified-charge engines. For motored operation, four sets of 60 consecutive LES cycles, with different operating conditions, are compared with experiments. LES is able to capture the wave dynamics of the ports and the in-cylinder pressure with a difference of 0.12%-2.5%, compared to experimental results. The LES velocity fields are compared with particle-image velocimetry measurements at six cutting planes. Based on the local and volume-averaged structure and magnitude indexes, it is found that LES is able to reproduce key flow events and capture large-scale in-cylinder flow structures, especially in high tumble/swirl conditions. Using proper orthogonal decomposition, LES shows that high tumble/swirl conditions produce low CCV flow fields. CCV of in-cylinder pressure ranged between 0.13% and 0.23%. For fired operation, and using the thickened flame model (TFM), 20 consecutive LES cycles of a homogeneous-charge engine operation mode are presented followed by spray-characterization in four different ambient conditions. These results lay the foundation for two stratified-charge engine operation modes, in which 20 and 35 consecutive LES cycles are compared with experiments, respectively. TFM-LES is extended for partially premixed flames and is able to reproduce experimental in-cylinder pressure (0.5%-10%), cyclic variability (20.5%-22.7%) in global and local quantities, local fuel vapor distributions, and heat release curves for homogeneous and stratified burn. Tuning TFM to reduce the burn rate increases the tendency to produce misfires, as well as the levels of CCV. Correlation analysis done on the stratified-charge LES results suggests that the influence of the early burn on the subsequent flame development is more subtle for stratified combustion compared to homogeneous combustion, that is the local conditions at the spark plug when the flame starts propagating are more influential than the conditions at spark timing, and that the injection event creates velocity conditions which might be favorable or unfavorable for the combustion event. The main contributions of this dissertation are extending TFM to highly stratified spray combustion, showing that LES can reproduce experimentally measured flow and combustion behavior in a realistic engine, including CCV, and analyzing LES to provide new insight into CCV and misfires of stratified-charge engines. Advisors/Committee Members: Advisor%22%29&pagesize-30">Daniel Connell Haworth, Dissertation Advisor/Co-Advisor, Daniel Connell Haworth, Committee Chair/Co-Chair, Jacqueline Antonia O'Connor, Committee Member, Yuan Xuan, Committee Member, Sven Schmitz, Outside Member, Stephen R Turns, Special Member, Robert John Santoro, Special Member, Karen Ann Thole, Program Head/Chair.

Subjects/Keywords: Internal Combustion Engines; Large-Eddy Simulation; Cycle-to-Cycle Variations; Stratified-Charge Combustion; Gasoline-Direct-Injection Engine

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

APA (6^th Edition):

Kazmouz, S. (2020). Large-Eddy Simulations of Motored Flow and Combustion in a Stratified-Charge Direct-Injection Spark-Ignition Engine. (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/17568xuk13

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

Chicago Manual of Style (16^th Edition):

Kazmouz, Samuel. “Large-Eddy Simulations of Motored Flow and Combustion in a Stratified-Charge Direct-Injection Spark-Ignition Engine.” 2020. Thesis, Penn State University. Accessed March 06, 2021. https://submit-etda.libraries.psu.edu/catalog/17568xuk13.

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

MLA Handbook (7^th Edition):

Kazmouz, Samuel. “Large-Eddy Simulations of Motored Flow and Combustion in a Stratified-Charge Direct-Injection Spark-Ignition Engine.” 2020. Web. 06 Mar 2021.

Vancouver:

Kazmouz S. Large-Eddy Simulations of Motored Flow and Combustion in a Stratified-Charge Direct-Injection Spark-Ignition Engine. [Internet] [Thesis]. Penn State University; 2020. [cited 2021 Mar 06]. Available from: https://submit-etda.libraries.psu.edu/catalog/17568xuk13.

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

Council of Science Editors:

Kazmouz S. Large-Eddy Simulations of Motored Flow and Combustion in a Stratified-Charge Direct-Injection Spark-Ignition Engine. [Thesis]. Penn State University; 2020. Available from: https://submit-etda.libraries.psu.edu/catalog/17568xuk13

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

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Open Access Theses and Dissertations