Dissertations / Theses on the topic 'Lean burn combustor'

In combustor design and development, the use of unsteady computational fluid dynamics (CFD) simulations of transient combustor aero-thermo-dynamics to provide an insight into the complex reacting flow-field is expensive in terms of computational time. A large number of such high-fidelity reactive CFD analyses of the objective and constraint functions are normally required in combustor design and optimisation process. Hence, traditional design strategies utilizing only high-fidelity CFD analyses are often ruled out, given the complexity in obtaining accurate flow predictions and limits on available computational resources and time. This necessitates a careful design of fast, reliable and efficient design strategies. Surrogate modeling design strategies, including Kriging models, are currently being used to balance the challenges of accuracy and computational resource to accelerate the combustor design process. However, its feasibility still largely relies on the total number of design variables, objective and constraint functions, as only high-fidelity CFD analyses are used to construct the surrogate model. This thesis explores these issues in combustor design by aiming to minimize the total number of high fidelity CFD runs and to accelerate the process of finding a good design earlier in the design process. Initially, various multi-fidelity design strategies employing a co-Kriging surrogate modeling approach were developed and assessed for performance and confidence against a traditional Kriging based design strategy, within a fixed computational budget. Later, a time-parallel combustor CFD simulation methodology is proposed, based on temporal domain decomposition, and further developed into a novel time-parallel co-Kriging based multi-fidelity design strategy requiring only a single CFD simulation to be setup for various fidelities. The performance and confidence assessment of the newly developed multi-fidelity strategies shows that they are, in general, competitive against the traditional Kriging based design strategy, and evidence exists of finding a good design early in the design optimisation process

In order to meet the increasingly strict emissions targets required in modern civil aviation, lean burn combustors are being pursued as a means to reduce the environmental impact of gas-turbine engines. By adopting a lean air/fuel mixture NOx production may be reduced. The increase in proportional amount of high pressure air entering directly into the combustor reduces the amount available for cooling of the combustor liner tiles. A reduced mass of air places restrictions on the porosity of cooling arrays, requiring a departure from applications of pedestal and slotted film cooling typically used to cool double skin combustor liners. An alternative approach applied to lean burn combustors places impingement and effusion arrays on the cold and hot skins respectively for cooling of both sides of the hot liner skin. Although impingement cooling is well established as a means of promoting forced convection cooling, there are many areas on a liner tile where cooling behaviour is not well characterised. Additionally, film cooling reduces combustive efficiency and increases the production of NOx and CO, prompting interest in reducing its use in combustor cooling. The research for this thesis has focussed on investigations into current and proposed geometries to identify methods to enhance cold side cooling in lean burn applications. A fully modelled combustor liner tile has been used for investigation into the impact of structural and pressure blockages on cold side cooling performance of an impingementeffusion array using a transient liquid crystal technique to measure heat transfer performance. Research has found structural blockages can reduce heat transfer performance to ~60% of typical values, with crossflow development due to pressure blockage producing similar reductions in Nusselt values to ~70% of typical. A second investigation explored enhanced cooling geometries combining a distributed impingement feed over roughened channels of pedestals at variable height (H/D) and pitch (P/D). A newly proposed 'Shielded Impingement' concept combines full height pedestals, to protect impingement jets from developing crossflow, with quarter height pedestals for turbulence enhancement of crossflow cooling. The research has found that Shielded Impingement geometries displayed the strongest cooling performance of all tested designs due primarily to increased downstream Nusselt numbers. Pressure losses were comparable to short pedestal geometries, with little apparent effect of full height pedestals. Low pressure losses mean that application to extended channels in line with the full tile geometry is possible.

This thesis describes an experimental investigation into ignition systems, their effects on the combustion process, and how the discharge is affected by the prevailing pressure, temperature and flow. The work is divided into four main areas, a comprehensive literature review, engine testing for ignition system suitability, non-flow rig testing (including erosion) and flow rig testing. The literature review concluded that the most practical ignition system for lean burn gas engines will continue to be based on the spark plug, but in the medium to long term, laser ignition may become viable. The measurement of the HT voltage and current is not straightforward, and appropriate methods have been identified. Capacitive and inductive ignition system types were compared in lean and diluted conditions on a single cylinder research engine of modern design at different engine loads and speeds. It was found that the most beneficial ignition system was an inductive ignition system, although that for some conditions, capacitive systems induced better engine performance with a fraction of the stored energy of the inductive alternative. Non flow tests showed that the early part of the spark discharge is sensitive to pressure and temperature effects, and as a consequence, the latter stages of the discharge are also affected. A correlation has been developed, for use with conventional nickel electrode spark plugs, to predict breakdown voltage as a function of pressure, temperature and gap. Experiments were carried out at elevated pressures in a stream of flowing air with capacitive and inductive ignition systems. Different electrode designs and orientations were also compared. It was shown that when exposed to a flow field, the discharge can be stretched which results in a shortened spark duration; in some cases the electrode can shield the discharge from flow field effects. This work showed that flow through the spark gap is a hindrance to the spark process, especially for longer duration systems. However for flame kernel growth, the literature review identified that flow is beneficial, serving to convect the kernel away from the electrodes, reducing the heat transfer from the flame. Analysis of the glow voltage history in the pressurised flow rig has been used to develop a correlation relating the voltage, current, flow velocity, pressure and time. This correlation was used to analyse the velocity records from the spark plug in a firing engine. The predicted velocities and turbulence intensity were in agreement with independent measurements.

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2004.
Includes bibliographical references (p. 95-97).
Lean operation of spark ignition (SI) automotive engines offers attractive performance incentives. Lowered combustion temperatures inhibit NO[sub]x pollutant formation while reduced manifold throttling minimizes pumping losses, leading to higher efficiency. These benefits are offset by the reduced combustion speed of lean mixtures, which can lead to high cycle-to-cycle variation and unacceptable engine behavior characteristics. Hydrogen-enhancement can suppress the undesirable consequences of lean operation by accelerating the combustion process, thereby extending the "lean limit." Hydrogen can be produced onboard the vehicle with a plasmatron fuel reformer device. Combustion optimization experiments focused on three key areas: the ignition system, charge motion in the inlet ports, and mixture preparation. The ignition system tests compared a standard inductive coil scheme against high-energy discharge systems. Charge motion experiments focused on the impact of turbulence patterns generated by conventional restrictor plates as well as novel inlet flow modification cones. The turbulent motion of each configuration was characterized using swirl and tumble flow benches. Mixture preparation tests compared a standard single-hole pintle injector against a fine atomizing 12-hole injector. Lastly, a further series of trials was also run to investigate the impact of high exhaust gas recirculation (EGR) dilution rates on combustion stability. Results indicate that optimizations of the combustion system in conjunction with hydrogen-enhancement can extend the lean limit of operation by roughly 25% compared against the baseline configuration. Nearly half of this improvement may be attributed to improvements in the combustion system.
(cont.) An inductive ignition system in conjunction with a high tumble-motion inlet configuration leads to the highest levels of combustion performance. Furthermore, hydrogen enhancement affects a nearly constant absolute improvement in the lean misfire limit regardless of baseline combustion behavior. Conversely, the amount of improvement in the point of peak engine NIMEP output is inversely related to the level of baseline performance.
by Joshua A. Goldwitz.
S.M.

This document is the statement of independent and original contribution to knowledge represented by the published works in partial fulfilment of the requirements of the University of Brighton for the degree of Doctor of Philosophy (by publication). The thesis reviews the impact of research work conducted between 1992 and 1998 on various concepts to improve the economy and emissions of gasoline engines in order to address environmental and legislative pressures. The research has a common theme, examining the dilution of the intake charge (with either recycled exhaust gas [EGR], excess air, or the two in combination) in both conventional port injected [MPI] and direct injection [G-DI] combustion systems. After establishing the current status of gasoline engine technology before the programme of research was started, the thesis concentrates on seven major pieces of research between 1992 and 1996. These explored a subsequently patented method of applying recycled exhaust gas to conventional port injected gasoline engines to improve their economy and emissions whilst staying compatible with three-way catalyst systems. Nine other studies are reviewed which took place between 1992 and 1999 covering other methods of improving gasoline engines, specifically direct injection and two-stroke operation. Together, all the studies provide a treatise on methods to improve the gasoline engine and the thesis allows a view from a broader perspective than was possible at the time each study was conducted. In particular, the review identifies a range of strategies that use elements of the research that can be used to improve economy and emissions. Four major categories of systems researched include: conventional stoichiometric MPI engines developed to tolerate high EGR rates [CCVS]; two-stroke G-DI engines; G-DI engines operating stoichiometrically with high EGR rates; and G-DI engines operating with high dilution from both excess air and EGR. The findings of the studies illustrate that although good fuel economy improvements and emissions can be obtained with EGR dilution of stoichiometric engines, the highest fuel economy improvements require lean deNOx aftertreatment [LNA] and these, in turn, require new aftertreatment technologies and preferably new fuel specifications. The development of suitable LNA and the cost of implementation of these approaches represents one of the main barriers to improving gasoline engine fuel economy and emissions.

Otto-engines in which the combustion chamber has richer fuel/air mix close to the ignition source and leaner charge further away from the ignition source are often called "stratified charge engines". Stratified charge can be used to increase the combustion speed in an internal combustion engine and thereby enable the engine to run on a fuel/air mix that would normally burn too slowly or not burn at all. The use of prechambers is one way to obtain stratified charge.

This thesis presents and uses methods for studying a prechamber more or less indepently from the rest of the engine.

When the prechamber is studied like an engine of itself, then the output of the "engine" is not mechanical power, but rather one or more hot jets into the main chamber. "Prechamber efficiencies" can be defined based on how much of the initial chemical energy is delivered as kinetic or thermal energy into the main chamber. Models of other important characteristics including the jet length and duration are also presented and used.

Natural gas is currently an attractive substitute for diesel fuel in the Heavy-Duty (HD) diesel transportation sector. This is primarily attributed to its cost effectiveness, but also its ability to reduce the amount of CO2 and harmful engine pollutants emitted into the atmosphere. Lean-burn dual-fuel engines substitute natural gas in place of diesel but typically suffer from high engine-out methane (CH4) emissions, particularly under low load operation. In response to this issue, this work set out to improve upon the efficiency and emissions of a lean-burn dual-fuel combustion system in an HD diesel/natural gas engine. Thermodynamic experimental engine testing was performed at various steady-state operating points in order to identify the most effective methods and technologies for improving emissions and efficiency. Low Temperature Combustion (LTC) along with several valvetrain and injection strategies were evaluated for benefits, with special attention paid to low load operating conditions. LTC was proven to be a useful method for decreasing methane emissions while simultaneously improving engine efficiency. The benefits of LTC were a function of load with the greatest advantages experienced under medium load operation. Additionally, the low load strategies tested were determined to be effective techniques for reducing methane emissions and could possibly extend the dual-fuel operating regime to lighter load conditions. Overall, no operating condition tested throughout the engine map resulted in a brake engine-out methane emissions level of less than 0.5 g/kWh at gas substitutions greater than approximately 75%. It is suggested that the limits of this particular lean-burn dual-fuel design were reached, and that it would likely require improvements to either the combustion system or exhaust after-treatment if Euro VI emissions levels for methane were to be achieved.

La ricerca nel campo dei motori a combustione interna è sempre più rivolta ad identificare una soluzione alternativa all’utilizzo dei combustibili derivati dal petrolio, per ragioni di carattere ambientale, politico ed economico. Il gas naturale (NG) è un combustibile ideale per motori a combustione interna, essendo caratterizzato da basso impatto ambientale e consumi ridotti rispetto ai combustibili convenzionali (benzina e gasolio). Inoltre esso è particolarmente adatto ad essere utilizzato in motori ad elevato rapporto di compressione volumetrico, ed è caratterizzato da un ampio campo di infiammabilità. Quest’ultimo aspetto promuove la combustione magra di miscele di aria e NG, ottenendo un ulteriore incremento di rendimento ed un’ulteriore diminuzione dei consumi. I motori dual-fuel NG/diesel permettono di estendere il limite magro d’infiammabilità rispetto ai motori ad accensione comandata alimentati a NG, ed allo stesso tempo consentono di ridurre il trade-off NOX-PM di cui soffrono i motori diesel. Tale tecnologia consiste nell’introduzione del NG come combustibile principale in un motore diesel. Una certa quantità di gasolio viene ancora iniettata, ed agisce come sorgente d’accensione per la miscela di aria e NG. La facilità di conversione rende la tecnologia dual-fuel particolarmente allettante come retrofit di motori diesel già esistenti che in futuro si troverebbero a non soddisfare i sempre più stringenti limiti sulle emissioni inquinanti. Nel presente lavoro, la combustione dual-fuel, con la sua inerente complessità, viene analizzata seguendo un approccio misto numerico-sperimentale. L’attività sperimentale ha come obiettivo l’analisi dei vantaggi e dei problemi connessi con la conversione di un motore diesel heavy-duty al funzionamento dual-fuel, sulla base delle prestazioni e delle emissioni inquinanti. L’attività numerica è caratterizza da un approccio misto 1-D/3-D, ed è stata inizialmente condotta per la corretta comprensione del complesso meccanismo di combustione in modalità dual-fuel. L’analisi multi-dimensionale (3-D) dettagliata del sistema cilindro–pistone è stata successivamente effettuata per la corretta rappresentazione dei fenomeni termo-fluidodinamici evolventi in camera di combustione. Una tale strategia permette la completa descrizione del comportamento dell’intero sistema motore e della combustione dual-fuel nel dettaglio.
The research activity on internal combustion engines is increasingly cast to find an alternative solution to reduce the wide utilization of petroleum fuels like diesel oil and gasoline, for environmental, political and economic concerns. Natural gas (NG) is an ideal fuel to be operated in internal combustion engines, since its characteristics allow for much lower environmental impact and reduced fuel consumption with respect the conventional fuels. It also is particularly suitable to be operated under high volumetric compression ratio engines, thus providing higher efficiency, and moreover it is characterized by a wide flammability range. This latter aspect promotes the employment of a lean burn strategy, thus further increasing the engine efficiency and reducing the exhaust emissions. The dual-fuel natural gas/diesel concept allows extending the lean flammability limit of NG with respect to SI-NG operations and simultaneously reducing the NOX-PM trade-off affecting diesel combustion. Such a technology consists in introducing NG as main fuel in a conventional diesel engine. A certain amount of diesel pilot injection is preserved to act as the ignition source for the air/NG mixture. The easiness of dual-fuel conversion makes such technology rather inviting especially as a retrofit for the existing diesel vehicles, which could not meet the more and more stringent emission regulations in the future. In the present study, the dual-fuel combustion process with its inherent complexity is investigated both from an experimental and a numerical point of view. The experimental activity has the main target to analyze the problems connected with the conversion of a heavy-duty diesel engine to dual-fuel operation, and to put into evidence the influence of the main engine parameters on performance and pollutants formation. The numerical activity, characterized by a mixed 1-D/3-D approach, has been carried out with the initial target of a correct understanding of the complex dual-fuel combustion mechanism. A detailed multi-dimensional simulation of the whole working cycle of the engine has been subsequently performed, to provide for the correct representation of the fluid-dynamic effect involved in dual-fuel operations. Such an approach allows for the complete description of the engine overall behavior and the dual-fuel combustion in detail.

[EN] This research work presents the study of a low pressure EGR loop influence on a SI gasoline turbocharged direct injection engine in steady and transient testing conditions, with an optimization process of the original engine calibration in order to minimize the engine fuel consumption when cooled EGR is introduced in steady testing conditions. The cooled EGR strategy was also evaluated operating in synergy with other fuel consumption reduction strategies, such as: lean burn, multi-injection, higher coolant temperature and in-cylinder induced swirl motion. To fulfill the main objectives of this research work, firstly, a methodical process was followed, where a global methodology was first developed in order to obtain high accuracy engine tests, based on the experimental tools chosen that could comply with the requirements of the testing conditions, and the appropriate theoretical tools and procedure to post-process the tests performed. Secondly, a specific methodology was developed for each stage of the study and testing conditions, taking into account optimization processes or parametric tests in order to study the effect of a single parameter on engine's outputs or optimize an engine parameter in order to minimize the engine fuel consumption. As a first stage of the study, a basic analysis of the impact of cooled EGR on the engine combustion, performance, air management and exhaust emissions is presented. Afterwards, an optimization of the combustion phasing in order to minimize the fuel consumption was performed, and therefore the potential of cooled EGR in order to reduce the engine fuel consumption was observed for low load, part load and full load engine conditions, for two different engine speeds. In addition, a study in transient conditions of the engine operating with cooled EGR was performed. NEDC cycles were performed with different EGR valve openings and therefore a comparison of different cooled EGR rates influence on the engine performance, air management and accumulated exhaust emissions was presented. The second stage, consisted in a methodology developed to optimize the VVT setting and injection timing, for part load engine conditions, in order to maximize the cooled EGR potential to reduce engine fuel consumption. After this optimization, a synergy analysis of the optimum engine condition operating with cooled EGR and three other engine fuel consumption reduction strategies was performed. These strategies were tested to investigate and evaluate the potential of increasing the cooled EGR operational range to further decrease the engine fuel consumption. Furthermore, a basic study of the potential to reduce the engine fuel consumption and impact on combustion, air management and exhaust emissions of a lean burn strategy, in part load engine conditions, was presented as introduction of the final study of the cooled EGR strategy operating in synergy with the lean burn strategy in order to investigate the potential to control the exhaust emissions and reduce the engine fuel consumption.
[ES] El objetivo de este trabajo de investigación es estudiar la influencia de un lazo de baja presión de EGR en las prestaciones de un motor de gasolina de encendido provocado turbosobrealimentado e inyección directa, en condiciones de ensayos estacionarios y transitorios, con un proceso de optimización de la calibración original del motor para minimizar el consumo de combustible del motor. La estrategia de "cooled EGR" fue también evaluada operando en sinergia con otras estrategias usadas para reducir el consumo de combustible del motor, entre ellas: mezcla pobre, múltiples inyecciones, operación a alta temperatura del fluido refrigerante del motor y movimiento de "swirl" inducido en el cilindro. Para cumplir con los objetivos mencionados, se siguió un proceso metódico donde previamente se desarrolló una metodología global para obtener resultados de indudable calidad, basados en el uso de herramientas experimentales que cumplieran con los requerimientos de las condiciones de ensayo, y las apropiadas herramientas teóricas y procedimiento para post-procesar los ensayos realizados. En segundo lugar, se desarrolló una metodología específica para cada etapa del estudio, teniendo en cuenta los procesos de optimización o estudios paramétricos que se pudieran realizar. Como primera etapa, se presenta un estudio básico del impacto del "cooled EGR" en la combustión, prestaciones, renovación de la carga y emisiones contaminantes del motor. Seguidamente, se procedió a la optimización del centrado de la combustión con la finalidad de minimizar el consumo de combustible del motor y poder analizar el potencial del "cooled EGR" como estrategia de reducción de consumo de combustible. El estudio presentado se realizó para baja, media y alta carga del motor con dos diferentes regímenes de giro del motor. Adicionalmente, se llevó a cabo un estudio del motor operando en condiciones transitorias con "cooled EGR". Se realizaron una serie de ensayos usando el ciclo NEDC como base y se probaron diferentes estrategias sencillas de control de la apertura de la válvula de EGR para analizar la influencia del "cooled EGR" en condiciones transitorias. La segunda etapa consiste en el desarrollo de una metodología para optimizar los parámetros del diagrama de distribución (VVT) y el inicio de inyección, para cargas medias del motor, con la finalidad de maximizar el potencial de reducción de consumo de combustible de la estrategia "cooled EGR". Una vez realizada la optimización, se llevó a cabo un estudio usando la configuración óptima encontrada, operando en sinergia con otras tres estrategias usadas para reducir el consumo de combustible del motor. Estas estrategias fueron evaluadas con la finalidad de incrementar el rango de operación de la estrategia "cooled EGR" para lograr reducir aún más el consumo de combustible del motor. Adicionalmente, se llevó a cabo un estudio básico sobre la influencia de operar con mezcla pobre en la combustión, prestaciones, renovación de la carga y emisiones contaminantes del motor, como introducción al último estudio llevado a cabo sobre la posibilidad de usar la estrategia de mezcla pobre en conjunto con la estrategia de "cooled EGR", con la finalidad de analizar el potencial de controlar las emisiones contaminantes y reducir el consumo de combustible del motor al mismo tiempo.
[CAT] L'objectiu d'este treball d'investigació és estudiar la influència d'un llaç de baixa pressió d'EGR en les prestacions d'un motor de gasolina d'encesa provocat turbosobrealimentat i injecció directa, en condicions d'assajos estacionaris i transitoris, amb un procés d'optimització del calibratge original del motor per a minimitzar el consum de combustible del motor. L'estratègia de "cooled EGR" va ser també avaluada operand en sinergia amb altres estratègies usades per a reduir el consum de combustible del motor, entre elles: mescla pobra, múltiples injeccions, operació a alta temperatura del fluid refrigerant del motor i moviment de `"swirl" induït en el cilindre. Per a complir amb els objectius mencionats, es va seguir un procés metòdic on prèviament es va desenrotllar una metodologia global per a obtindre resultats d'indubtable qualitat, basats en l'ús de ferramentes experimentals que compliren amb els requeriments de les condicions d'assaig, i les apropiades ferramentes teòriques i procediment per a post- processar els assajos realitzats. En segon lloc, es va desenrotllar una metodologia específica per a cada etapa de l'estudi, tenint en compte els processos d'optimització o estudis paramètrics que es pogueren realitzar. Com a primera etapa, es presenta un estudi bàsic de l'impacte del "cooled EGR" en la combustió, prestacions, renovació de la càrrega i emissions contaminants del motor. A continuació, es va procedir a l'optimització del centrat de la combustió amb la finalitat de minimitzar el consum de combustible del motor i poder analitzar el potencial del "cooled EGR" com a estratègia de reducció de consum de combustible. L'estudi presentat es va realitzar per a baixa, mitja i alta càrrega del motor amb dos diferents règims de gir del motor. Addicionalment, es va dur a terme un estudi del motor operand en condicions transitòries amb "cooled EGR". Es van realitzar una sèrie d'assajos usant el cicle NEDC com a base i es van provar diferents estratègies senzilles de control de l'obertura de la vàlvula d'EGR per a analitzar la influència del "cooled EGR" en condicions transitòries. La segona etapa consistix en el desenrotllament d'una metodologia per a optimitzar els paràmetres del diagrama de distribució (VVT) i l'inici d'injecció, per a càrregues mitges del motor, amb la finalitat de maximitzar el potencial de reducció de consum de combustible de l'estratègia "cooled EGR". Una vegada realitzada l'optimització, es va dur a terme un estudi usant la configuració òptima trobada, operant en sinergia amb altres tres estratègies usades per a reduir el consum de combustible del motor. Estes estratègies van ser avaluades amb la finalitat d'incrementar el rang d'operació de l'estratègia "cooled EGR" per a aconseguir reduir encara més el consum de combustible del motor. Addicionalment, es va dur a terme un estudi bàsic sobre la influència d'operar amb mescla pobra en la combustió, prestacions, renovació de la càrrega i emissions contaminants del motor, com a introducció a l'últim estudi dut a terme sobre la possibilitat d'usar l'estratègia de mescla pobra en conjunt amb l'estratègia de "cooled EGR", amb la finalitat d'analitzar el potencial de controlar les emissions contaminants i reduir el consum de combustible del motor al mateix temps.
Rivas Perea, ME. (2016). Assessment of fuel consumption reduction strategies on a gasoline turbocharged direct injection engine with a cooled EGR system [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/68497
TESIS

Combustion with a high surface area continuous solid immersed within the flame, referred to as combustion in porous media, is an innovative approach to combustion as the solid within the flame acts as an internal regenerator distributing heat from the combustion byproducts to the upstream reactants. By including the solid structure, radiative energy extraction becomes viable, while the solid enables a vast extension of flammability limits compared to conventional flames, while offering dramatically reduced emissions of NOx and CO, and dramatically increased burning velocities. Efforts documented within are used for the development of a streamlined set of design principles, and characterization of the flame's behavior when operating under such conditions, to aid in the development of future combustors for lean burn applications in open flow systems. Principles described herein were developed from a combination of experimental work and reactor network modeling using CHEMKIN-PRO. Experimental work consisted of a parametric analysis of operating conditions pertaining to reactant flow, combustion chamber geometric considerations and the viability of liquid fuel applications. Experimental behavior observed, when utilizing gaseous fuels, was then used to validate model outputs through comparing thermal outputs of both systems. Specific details pertaining to a streamlined chemical mechanism to be used in simulations, included within the appendix, and characterization of surface area of the porous solid are also discussed. Beyond modeling the experimental system, considerations are also undertaken to examine the applicability of exhaust gas recirculation and staged combustion as a means of controlling the thermal and environmental output of porous combustion systems. This work was supported by ACS PRF "51768-ND10 and NSF IIP 1343454.
M.S.M.E.
Masters
Mechanical and Aerospace Engineering
Engineering and Computer Science
Mechanical Engineering; Thermo-Fluids Track