Tesis sobre el tema "Compression Ignition"
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SANCHEZ, FERNANDO ZEGARRA. "COMPRESSION IGNITION OF ETHANOL-POWERED IN RAPID COMPRESSION MACHINE". PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2016. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=29324@1.
Texto completoCOORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
PROGRAMA DE EXCELENCIA ACADEMICA
Com o passar do tempo, a humanidade tem uma maior dependência na geração de energia, utilizada para promoção de conforto, transporte e outros. Com a finalidade de resolver este aumento de demanda, novas fontes eficientes, de preferência renováveis, estão sendo pesquisadas. O transporte é uma das atividades que tem maior dependência dos combustíveis fósseis, além de ser também um dos maiores geradores de gases de efeito estufa. É por isso, que em diversas partes do mundo, o homem pesquisa novas fontes de energia renováveis que possam ser substitutas dos atuais tradicionais usados no transporte. Sabe-se, que os motores Diesel são mais eficientes com relação aos motores Otto. Devido a este fato, há mais 30 anos pesquisam-se e desenvolvem-se sistemas de ignição por compressão, movidos com combustíveis renováveis, o qual permita a diminuição da dependência dos combustíveis fósseis e garanta a redução de gases de efeito estufa. O etanol é um candidato para substituir o oleo Diesel, mas tem que se levar em conta algumas alterações (aumento da relação de compressão, adição de melhoradores da autoignição, etc.) antes de ser utilizado nos motores Diesel. Com base nisto, a presente tese apresenta uma nova proposta, utilizar como melhorador da autoignição do etanol o n-butanol. Para tal propósito se desenvolveu diversos testes com diversas relações de compressão, percentuais em massa de aditivo na mistura de etanol e diversos avanços da injeção. Os testes foram realizados em uma máquina de compressão rápida (MCR) com misturas de etanol e polietilenoglicol 400 e 600, n-butanol, além dos testes refenciais com óleo Disel e ED95. Os resultados mostram que o n-butanol, com uma participação de 10 por cento na mistura, pode ser utilizado como melhorador da autoignição do etanol em sistemas de ignição por compressão.
Over time, humanity has developed a greater reliance inpower generation, used to promoter comfort, transport and others. In order to address this increased demand new efficient sources are being searched, in preference, renewable sources. Transportation is one of the activities that have greater reliance on fossil fuels as well as being one of the largest generators of greenhouse gases. Therefore, in many parts of the world men are engaged in the search of new renewable energy sources that can substitute the current one used in transport. It is known that diesel engines are more efficient in comparison to the Otto engime. Due to this fact, for more than 30 years research has been conducted in order to develop ignition systems by compression, powered with renewable fuels, which reduces the dependence on fossil fuels and the emission of greenhouse gases. Ethanol is a viable candidate to replace diesel oil, but some improvements have to be accounted for before it s used in diesel engines, improvements such as the increase in compression ratio, adding auto-ignition improves, etc. Based on the facts presented, this thesis offers a new proposal, the use of n-butanol as an auto-ignition improver for ethanol. For this purpose several tests have been executed with various compression ratios, mass percentage of additive in the mixture off ethanol and many start of injections. The tests were performed in a rapid compression machine (RCM) with mixtures of ethanol and polyethylene glycol 400 and 600, and n-butanol inaddition to the reference test with diesel oil and ED95. The results show that n-butanol with a 10 per cent share of the mixture, can be used as an auto ignition improver for ethanol in compression ignition systems.
Hahn, Tairin. "Ignition study in rapid compression machine". Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/46641.
Texto completoIncludes bibliographical references (leaves 79-81).
As it becomes more and more difficult to find "easy" oil, various alternative fuels are introduced to the markets. These fuels have chemical properties that are different from the traditional gasoline and diesel fuels so that engine efficiency and other engine behaviors may be affected To improve engine efficiency and to identify which alternative fuel is the cleanest fuel solution, it is necessary to compile information about the ignition delay, which governs auto-ignition in spark-ignition (SI), compression-ignition (CI) and homogeneous charge compression-ignition (HCCI) engines. In this study, we measured ignition delay on the Rapid Compression Machine (RCM). RCM is a single-stroke device, which compresses uniform mixtures to engine-like condition. We can interpret from the pressure the detailed heat release process. A comprehensive ignition delay database of toluene/n-heptane mixtures and gasoline/ethanol mixtures was established The data allow us to calculate the auto-ignition behavior in engines. Depending on application the correct choice of alternative fuels may be made.
by Tairin Hahn.
Mech.E.
Roberts, Philip John. "Fuel and residual effects in spark ignition and homogeneous charge compression ignition engines". Thesis, University of Leeds, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.530821.
Texto completoZeraati, Rezaei Soheil. "Experimental investigation of a premixed compression ignition engine". Thesis, University of Birmingham, 2016. http://etheses.bham.ac.uk//id/eprint/7037/.
Texto completoLOAIZA, JUAN CARLOS VALDEZ. "REACTIVITY CONTROLLED COMPRESSION IGNITION OF DIESEL FUEL AND ETHANOL IN RAPID COMPRESSION MACHINE". PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2014. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=35559@1.
Texto completoCONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO
Serão necessários muitos anos para que os biocombustíveis sejam capazes de substituir integralmente os derivados fósseis. Este trabalho visa estudar formas alternativas de conversão de energia contida nos combustíveis utilizados em motores de combustão interna. Maiores eficiências na conversão da energia contida no combustível e uma menor emissão dos gases de exaustão são benefícios associados à ignição por compressão de reatividade controlada, RCCI, onde dois fluidos com diferentes reatividades são introduzidos na câmara de combustão em instantes diferentes. Optou-se pelo uso de uma máquina de compressão rápida, MCR, capaz de controlar parâmetros relevantes, como taxa de compressão, pressões, tempos de injeção, que foi adaptada para receber dois sistemas de injeção direta na câmara de combustão. Como segundo combustível, que substitui parcialmente o óleo diesel, que é empregado tradicionalmente em motores de ignição por compressão, optou-se pelo etanol hidratado. Os estudos revelaram que diferentes formas de injeção dos dois combustíveis produzem processos muito diferentes, para as mesmas quantidades de combustíveis injetados. Os resultados são apresentados na forma de pressão indicada como função do ângulo equivalente, bem como calor liberado e atraso de ignição. Experiências foram conduzidas para uma ou duas injeções de etanol por ciclo, em diferentes tempos. Altas razões de substituição do combustível fóssil foram obtidas, quando comparadas com a técnica de fumigação, onde o segundo combustível é misturado externamente ao ar de combustão.
Many years will be needed for biofuels or other renewable sources to be able to fully replace fossil fuels. This work aims to study alternative ways of converting energy contained in fuels used in internal combustion engines. Higher efficiencies in converting the energy contained in the fuel and lower emission of harmful exhaust gases are benefits associated with the Reactivity Controlled Compression Ignition, known for RCCI. In this type of combustion, two fluids with different ignition-reactivity characteristics are introduced into the combustion chamber at different times. To better understand this phenomenon, it was used a RCM, that is able to control, more easily, relevant parameters such as compression ratio, temperatures, pressures, injection times etc. As a second fuel, which partially replaces the diesel, which is traditionally used in compression ignition engines, it was used the ethanol. The RCM was then adapted to receive two systems for direct injection into the combustion chamber. Studies have shown that different forms of injection of the two fuels produce very different processes to the same amount of fuel injected. The results are presented in the form of indicated pressure as a function of position. Heat released and ignition delay are also presented. Experiments were conducted for one or two injections of ethanol per cycle at different times. High substitution rates of the fossil fuel were obtained when compared to injections of external mixtures of diesel and ethanol or fumigation technique, where the second fuel is mixed externally with the combustion air.
Alqahtani, Ali Mubark. "Computational studies of homogeneous charge compression ignition, spark ignition and opposed piston single cylinder engines". Thesis, University of Birmingham, 2017. http://etheses.bham.ac.uk//id/eprint/7899/.
Texto completoSullivan, Morgen Paul. "Study of lubrication oil ignition in a rapid compression machine under sporadic pre-ignition conditions". Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/100352.
Texto completoCataloged from PDF version of thesis.
Includes bibliographical references (pages 95-97).
In recent years, the industry has shifted toward down-sizing and turbo-charging spark ignition (SI) engines in an effort to increase fuel conversion efficiency. However, this has given rise to a destructive phenomenon known as sporadic pre-ignition (SPI). At low cranking speeds and high loads, engines have been observed to knock violently for brief and infrequent intervals. If allowed to continue, these periods of knock will result in a destroyed engine. This study looks at the propensity of lube oil vapor appearing in the cylinder as a cause for this phenomenon. The theory is that a local oil vapor/air mixture pocket may auto-ignite and start a flame in the charge. The pre-ignition would produce extreme knock. A rapid compression machine (RCM) was used to simulate this scenario and determine if oil vapor can cause SPI, and if so, to relate the auto-ignition tendency to the oil properties. The RCM was used to measure the ignition delay of a cloud of oil vapor in a stoichiometric gasoline/air mixture. The ignition delays were then correlated to chemical and physical properties of the oils. Finally, the effect of diluting the mixture was assessed. The results suggest that lube oil is a plausible source of SPI. The oil ignition delay times are sufficiently short to produce extreme pre-ignition consistent with SPI. Further supporting evidence lies in the fact that oil ignition delay times concur with SPI behavior in engines. It was found that the base stock, degradation, and chemical additives all play a role in oil ignition delay times. The results also demonstrate. that dilution significantly slows auto-ignition of the oil.
by Morgen Paul Sullivan.
S.M.
Angelos, John P. (John Phillip). "Fuel effects in homogeneous charge compression ignition (HCCI) engines". Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/50615.
Texto completoIncludes bibliographical references (p. 209-217).
Homogenous-charge, compression-ignition (HCCI) combustion is a new method of burning fuel in internal combustion (IC) engines. In an HCCI engine, the fuel and air are premixed prior to combustion, like in a spark-ignition (SI) engine. However, rather than using a spark to initiate combustion, the mixture is ignited through compression only, as in a compression-ignition (CI) engine; this makes combustion in HCCI engines much more sensitive to fuel chemistry than in traditional IC engines. The union of SI- and CI-technologies gives HCCI engines substantial efficiency and emissions advantages. However, one major challenge preventing significant commercialization of HCCI technology is its small operating range compared to traditional IC engines. This project examined the effects of fuel chemistry on the size of the HCCI operating region, with an emphasis on the low-load limit (LLL) of HCCI operability. If commercialized, HCCI engines will have to operate using standard commercial fuels. Therefore investigating the impact of fuel chemistry variations in commercial gasolines on the HCCI operability limits is critical to determining the fate of HCCI commercialization. To examine these effects, the operating ranges of 12 gasolines were mapped in a naturally-aspirated, single-cylinder HCCI engine, which used negative valve overlap to induce HCCI combustion. The fuels were blended from commercial refinery streams to span the range of market-typical variability in aromatic, ethanol, and olefin concentrations, RON, and volatility. The results indicated that all fuels achieved nearly equal operating ranges. The LLL of HCCI operability was completely insensitive to fuel chemistry, within experimental measurement error. The high-load limit showed minor fuel effects, but the trends in fuel performance were not consistent across all the speeds studied. These results suggest that fuel sensitivity is not an obstacle to auto-makers and/or fuel companies to introducing HCCI technology.
(cont.) Developing an understanding of what causes an HCCI engine to misfire allows for estimation of how fuel chemistry and engine operating conditions affect the LLL. The underlying physics of a misfire were studied with an HCCI simulation tool (MITES), which used detailed chemical kinetics to model the combustion process. MITES was used to establish the minimum ignition temperature (Tmisfire) and full-cycle, steady-state temperature (Tss) for a fuel as a function of residual fraction. Comparison of Tmisfire and Tss near the misfire limit showed that Tss approaches Tmisfire quite closely (to within ~ 14 K), suggesting that the primary cause of a misfire is insufficient thermal energy needed to sustain combustion for multiple cycles. With this relationship, the effects of engine speed and fuel chemistry on the LLL were examined. Reducing the engine speed caused a reduction in T, which allowed fuel chemistry effects to be more apparent. This effect was also observed experimentally with 2 primary reference fuels (PRFs): PRF60 and PRF90. At 1000 RPM, PRF60 obtained a substantially lower (~30%) LLL than PRF90, but at speeds >/= 1500 RPM, fuel ignitability had no effect on the LLL. Fuel chemistry was shown to influence the LLL by increasing both Tmisfire and Tss for more auto-ignition resistant fuels. However, the extent to which fuel chemistry affects these temperatures may not be equivalent. Therefore, the relative movement of each temperature determines the extent to which fuel chemistry impacts the LLL.
by John P. Angelos.
Ph.D.
Bhave, Amit. "Stochastic reactor models for homogeneous charge compression ignition engines". Thesis, University of Cambridge, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.616153.
Texto completoMonsalve, Serrano Javier. "Dual-fuel compression ignition: towards clean, highly efficient combustion". Doctoral thesis, Universitat Politècnica de València, 2016. http://hdl.handle.net/10251/75109.
Texto completoLas cada vez más restrictivas normativas anticontaminantes, junto con la demanda de motores con menor consumo de combustible por parte de los usuarios, imponen un claro objetivo a investigadores y fabricantes de motores: la búsqueda de la máxima eficiencia con los mínimos niveles de emisiones contaminantes. La combustión diésel convencional ofrece una alta eficiencia, pero a su vez da lugar a elevadas emisiones de NOx y hollín que requieren del uso de sistemas de postratamiento para reducir los niveles finales emitidos al ambiente. Dado que estos sistemas incurren en mayores costes de adquisición y operación del motor, la comunidad científica está trabajando en el desarrollo distintas estrategias para reducir la generación de estos contaminantes durante el propio proceso de combustión. La literatura demuestra que los nuevos modos de combustión basados en promover bajas temperaturas durante este proceso, ofrecen simultáneamente una elevada eficiencia y muy bajos niveles de NOx y hollín. Sin embargo, tras años de investigación, se puede llegar a la conclusión de que estas técnicas no pueden ser aplicadas en todo el rango de operación del motor debido a, entre otros, factores como el escaso control sobre el proceso de combustión. En los últimos años, se ha demostrado que la técnica de combustión dual-fuel permite superar esta limitación gracias al grado de libertad adicional que supone la capacidad de modular la reactividad del combustible en función de las condiciones de operación del motor. Esta característica, junto con los casi nulos niveles de NOx y hollín que proporciona, ha despertado un gran interés sobre la comunidad científica. En este sentido, trabajos precedentes confirman las ventajas que este modo de combustión ofrece, demostrando a su vez que aún existen una serie de limitaciones por abordar, así como cierto margen por explotar para mejorar el potencial de este concepto. La presente Tesis Doctoral plantea como objetivo general el contribuir a la comprensión del modo de combustión dual-fuel, y de manera particular explorar distintas vías con objeto de mejorar su eficiencia. Para ello, se han evaluado de manera experimental diferentes opciones que van desde la modificación de los parámetros de operación del motor, hasta diseños específicos de la geometría del pistón o el uso de combustibles alternativos. Tratando de responder algunas de las cuestiones encontradas en la literatura, en cada uno de los estudios se ha realizado un análisis detallado de la influencia del parámetro en cuestión sobre la operación del motor a baja carga, y a su vez se ha comprobado la capacidad de cada una de estas opciones de extender la operación del motor hacia cargas más elevadas. Cabe destacar que el análisis de ciertos resultados se ha apoyado en cálculos numéricos CFD, los cuales han permitido entender ciertos fenómenos locales que ocurren durante el proceso de combustión dual-fuel, y que no pueden ser confirmados únicamente desde el punto de vista experimental. Finalmente, teniendo en cuenta el conocimiento adquirido en los diferentes estudios realizados, el último capítulo de resultados se ha dedicado a evaluar la capacidad de operación del concepto dual-fuel en todo el rango de funcionamiento del motor, así como a identificar las posibles limitaciones que esta técnica presenta desde el punto de vista tecnológico.
Les cada vegada més restrictives normatives anticontaminants, juntament amb la demanda de motors amb menor consum de combustible per part dels usuaris, imposen un clar objectiu a investigadors i fabricants de motors: la cerca de la màxima eficiència amb els mínims nivells d'emissions contaminants. La combustió dièsel convencional ofereix una alta eficiència, però al seu torn dóna lloc a elevades emissions de NOx i sutge que requereixen de l'ús de sistemes de postractament per a reduir els nivells finals emesos a l'ambient. Aquests sistemes incorren en majors costos d'adquisició i operació del motor, per la qual cosa de forma paral·lela, la comunitat científica està treballant en el desenvolupament de diferents estratègies per a reduir la generació d'aquests contaminants durant el propi procés de combustió. La literatura demostra que les noves tècniques de combustió basades a promoure baixes temperatures durant aquest procés, ofereixen simultàniament una elevada eficiència i molt baixos nivells de NOx i sutge. No obstant açò, després d'anys de recerca, es pot arribar a la conclusió que aquestes tècniques no poden ser aplicades en tot el rang d'operació del motor a causa de, entre uns altres, factors com l'escàs control sobre el procés de combustió. En els últims anys, s'ha demostrat que la tècnica de combustió dual-fuel permet superar aquesta limitació gràcies al grau de llibertat addicional que suposa la capacitat de modular la reactivitat del combustible en funció de les condicions d'operació del motor. Aquesta característica, juntament amb els quasi nuls nivells de NOx i sutge que proporciona, ha despertat un gran interès sobre la comunitat científica. En aquest sentit, treballs precedents confirmen els avantatges que aquesta tècnica de combustió ofereix, demostrant al seu torn que encara existeixen una sèrie de limitacions per abordar, així com cert marge per explotar per a millorar el potencial d'aquest concepte. La present Tesi Doctoral planteja com a objectiu general el contribuir a la comprensió de la tècnica de combustió dual-fuel, i de manera particular explorar diferents vies a fi de millorar la seua eficiència. Per a açò, s'han avaluat de manera experimental diferents opcions que van des de la modificació dels paràmetres d'operació del motor, fins a dissenys específics de la geometria del pistó o l'ús de combustibles alternatius. Tractant de respondre algunes de les qüestions trobades en la literatura, en cadascun dels estudis s'ha realitzat una anàlisi detallada de la influència del paràmetre en qüestió sobre l'operació del motor a baixa càrrega, i al seu torn s'ha comprovat la capacitat de cadascuna d'aquestes opcions d'estendre l'operació del motor cap a càrregues més elevades. Cal destacar que l'anàlisi de certs resultats s'ha recolzat en càlculs numèrics CFD, els quals han permès entendre certs fenòmens locals que ocorren durant el procés de combustió dual-fuel, i que no poden ser confirmats únicament des del punt de vista experimental. Finalment, tenint en compte el coneixement adquirit en els diferents estudis realitzats, l'últim capítol de resultats s'ha dedicat a avaluar la capacitat d'operació del concepte dual-fuel en tot el rang de funcionament del motor, així com a identificar les possibles limitacions que aquesta tècnica presenta des del punt de vista tecnològic.
Monsalve Serrano, J. (2016). Dual-fuel compression ignition: towards clean, highly efficient combustion [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/75109
TESIS
Kawambwa, S. J. M. "Performance and combustion of ethanol in a high-compression, direct-injection, compression-ignition engine". Thesis, University of Surrey, 1993. http://epubs.surrey.ac.uk/981/.
Texto completoAyala, Ferran A. (Ferran Alberto) 1976. "Data base generation and modeling of Homogeneous Charge Compression Ignition using a rapid compression machine". Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/88882.
Texto completoRöhl, Olaf [Verfasser]. "Low Temperature Chemistry in Gasoline Compression Ignition Engines / Olaf Röhl". Aachen : Shaker, 2010. http://d-nb.info/1120864054/34.
Texto completoHong, Guang. "Feedback control of transient smoke emissions from compression ignition engines". Thesis, University of Cambridge, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.304278.
Texto completoAl, Qahtani Yasser. "Particulate matter characterization and control in premixed compression ignition engines". Thesis, University of Birmingham, 2017. http://etheses.bham.ac.uk//id/eprint/7187/.
Texto completoKontarakis, George A. "Homogeneous charge compression ignition in four-stroke internal combustion engines". Thesis, University of Cambridge, 2001. https://www.repository.cam.ac.uk/handle/1810/272293.
Texto completoResor, Michael Irvin. "COMPUTATIONAL INVESTIGATION OF ROTARY ENGINE HOMOGENEOUS CHARGE COMPRESSION IGNITION FEASIBILITY". Wright State University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=wright1419010366.
Texto completoMaterego, Myeji Chrysostom. "Auto-ignition characterisation of synthetic fuels via Rapid Compression Machine". Thesis, University of Leeds, 2015. http://etheses.whiterose.ac.uk/12929/.
Texto completoKaragiorgis, Stelios. "Dynamic modeling and transient control of Homogeneous Charge Compression Ignition engines". Thesis, University of Cambridge, 2008. https://www.repository.cam.ac.uk/handle/1810/252072.
Texto completoAntunes, Jorge Manuel Gomes. "The use of hydrogen as a fuel for compression ignition engines". Thesis, University of Newcastle Upon Tyne, 2011. http://hdl.handle.net/10443/1365.
Texto completoCCACYA, ANTHONY OSWALDO ROQUE. "EXPERIMENTAL STUDY OF HOMOGENEOUS MIXTURE COMPRESSION IGNITION IN INTERNAL COMBUSTION ENGINES". PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2010. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=17159@1.
Texto completoCom o intuito de reduzir as emissões e melhorar a combustão em uma maior faixa de rotação e carga de um motor, foi proposto o estudo da combustão por compressão de misturas homogêneas (HCCI), este processo apresenta altas eficiências e baixas emissões, principalmente de NOx e fuligem. Assim, o objetivo do presente trabalho é a determinação das faixas de operação estável em um motor diesel, de alta taxa de compressão (20:1). O combustível utilizado foi gasolina tipo A, tendo em vista a sua grande produção, além das características de auto-ignição. Para atingir o objetivo proposto foram controladas a temperatura de entrada do ar e a quantidade de combustível da mistura, o que foi implementado sem modificação estrutural do motor. Os ensaios foram realizados com uma temperatura de alimentação entre 75 e 95 ºC, com rotação entre 1200 e 2200 RPM. Os valores para o fator lambda variaram, em função de um processo de combustão estável, entre 2 e 4. São apresentados os resultados experimentais obtidos em um dinamômetro de bancada, sobre os quais se fez uma análise do rendimento, para a faixa de melhor estabilidade da combustão. Para a mesma faixa foi realizada uma análise das curvas de pressão x tempo, caracterizando a auto-ignição como função da temperatura do ar e da riqueza da mistura. Os melhores rendimentos encontrados situam-se ao redor de 36,5 %, para uma temperatura de ingresso de 85 °C, para as maiores rotações pesquisadas.
The present study of homogeneous mixture compression ignition (HCCI) was proposed in order to reduce emissions and improve combustion at a higher speed range and load, this process has high efficiency and low emissions mainly NOx and soot. Therefore, the aim of this study was to determine the ranges of stable operation in a diesel engine of high compression ratio (20:1), operating in HCCI. The fuel used was gasoline type A, given its large production, besides the good characteristics of auto-ignition. To achieve this purpose were controlled inlet air temperature and the amount of fuel in the mixture, these were implemented without structural modification of the engine. The tests were conducted with a feed temperature between 75 and 95 ° C, with rotation between 1200 and 2200 RPM. The values for the lambda factor varied between 2 and 4, as a function of a stable combustion process. The experimental results here reported were obtained on a dynamometer bench, on which, it was made a performance analysis for the better stability combustion range. Additionally for this range, an analysis of the curves of pressure vs. time was performed, characterizing the auto-ignition as a function of air temperature and the richness of the mixture. The best results found are located around 36.5% at an intake temperature of 85 ° C for the highest speed studied.
Park, Pyongwan. "Rapid compression machine measurements of ignition delays for primary reference fuels". Thesis, Massachusetts Institute of Technology, 1990. http://hdl.handle.net/1721.1/14068.
Texto completoFang, Ming. "Analysis of Variability and Injection Optimization of a Compression Ignition Engine". The Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=osu1250532113.
Texto completoOak, Sushil Shreekant. "Second law analysis of premixed compression ignition combustion in a diesel engine using a thermodynamic engine cycle simulation". Texas A&M University, 2008. http://hdl.handle.net/1969.1/86040.
Texto completoWhite, Timothy Ross Mechanical & Manufacturing Engineering Faculty of Engineering UNSW. "Simultaneous diesel and natural gas injection for dual-fuelling compression-ignition engines". Awarded by:University of New South Wales. School of Mechanical and Manufacturing Engineering, 2006. http://handle.unsw.edu.au/1959.4/25233.
Texto completoWu, Ning. "Autoignition and emission characteristics of gaseous fuel direct-injection compression-ignition combustion". Thesis, University of British Columbia, 2007. http://hdl.handle.net/2429/357.
Texto completoConstandinides, George. "Thermal management and control of a homogeneous charge compression ignition (HCCI) engine". Thesis, University of Birmingham, 2014. http://etheses.bham.ac.uk//id/eprint/4900/.
Texto completoSu, Haiyun. "Stochastic reactor models for simulating direct injection homogeneous charge compression ignition engines". Thesis, University of Cambridge, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.608887.
Texto completoCrawford, Morgan H. "Feasibility and Emissions of Compression Ignition Engines Fueled with Waste Vegetable Oil". [Tampa, Fla.] : University of South Florida, 2003. http://purl.fcla.edu/fcla/etd/SFE0000193.
Texto completoIslam, Muhammad Aminul. "Microalgae: An alternative source of biodiesel for the compression ignition (CI) engine". Thesis, Queensland University of Technology, 2014. https://eprints.qut.edu.au/79551/4/Muhammad%20Aminul%20Islam%20Thesis.pdf.
Texto completoLin, Wei. "The Ignition of Methane and Coal Dust by Air Compression - The Experimental Proof". Thesis, Virginia Tech, 1997. http://hdl.handle.net/10919/36740.
Texto completoMaster of Science
Aksu, Cagdas. "Performance Analysis Of A Compression Ignition Internal Combustion Engine Using Superheated Ethanol Vapor". Master's thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12613255/index.pdf.
Texto completoakar. The results will indicate if the suggested concept can be applicable.
Birger, Nicholas Joseph. "Flow characteristics of gas-blast fuel injectors for direct-injection compression-ignition engines". Thesis, University of British Columbia, 2010. http://hdl.handle.net/2429/25752.
Texto completoNamasivayam, Ashand Mitra. "Combustion, performance and emissions characteristics of compression-ignition engines fuelled by sustainable fuels". Thesis, Queen Mary, University of London, 2011. http://qmro.qmul.ac.uk/xmlui/handle/123456789/668.
Texto completoPRADELLE, FLORIAN ALAIN YANNICK. "USE OF BIOFUELS IN COMPRESSION IGNITION ENGINES: POTENTIAL OF DIESEL-BIODIESEL-ETHANOL BLENDS". PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2017. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=29914@1.
Texto completoCOORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO
FUNDAÇÃO DE APOIO À PESQUISA DO ESTADO DO RIO DE JANEIRO
PROGRAMA DE EXCELENCIA ACADEMICA
BOLSA NOTA 10
Para substituir parcialmente a demanda em óleo diesel de origem fóssil, reduzir os elevados custos de importação e respeitar as normas ambientais, políticas sustentáveis já levaram a substituir parcialmente óleo diesel por biodiesel. Entretanto, outras tecnologias, como as misturas diesel-biodiesel-etanol, estão sendo investigadas. O principal desafio dessas misturas consiste em melhorar a miscibilidade e a estabilidade do álcool no óleo diesel. No presente trabalho, formulou-se um aditivo original, a partir de compostos renováveis, que permitiu melhorar a faixa de concentração de etanol anidro dentro de óleo diesel com 15 por cento em volume de biodiesel e de temperatura onde observa-se misturas estáveis. Diversas propriedades físico-químicas das misturas aditivadas foram medidas em uma larga faixa de concentração de etanol para avaliar os aspetos de consumo, qualidade da combustão, comportamento a baixa temperatura, interação entre fluido e superfície, e segurança. Os resultados obtidos mostraram que misturas com, pelo menos, 1,0 por cento em volume de aditivo e até 20 por cento em volume de etanol anidro são estáveis para temperaturas superiores a 10 graus Celsius e respeitam a maioria das especificações brasileiras atuais para óleo diesel. Ensaios experimentais em um motor de ignição por compressão MWM 4.10 TCA (Euro III) foram realizados com estas misturas. Os resultados obtidos mostraram que a substituição do óleo diesel altera as características da combustão: o crescente teor de etanol leva ao aumento do atraso de ignição, à liberação de calor mais rápida e à diminuição da pressão máxima. Mesmo nessas condições não otimizadas de injeção e de combustão, os resultados mostraram uma melhor conversão da energia química no etanol para produzir potência efetiva, comparado com os valores encontrados nos motores flex fuel de ciclo Otto, além de um pequeno aumento no rendimento térmico do motor.
In order to partially replace the demand of fossil diesel fuels, to reduce high import costs and to comply with environmental standards, sustainable policies have led to partially replace diesel fuel by biodiesel. However, other technologies, such as diesel-biodiesel-ethanol mixtures, are being investigated. The major challenge of these mixtures is to improve the miscibility and the stability of alcohol in diesel fuel. In this study, an original additive, from renewable compounds, improved the miscibility of anhydrous ethanol in diesel fuel with 15 per cent by volume of biodiesel and temperature in which stable mixtures were observed. Several physicochemical properties of the additivated mixtures were measured in a large range of ethanol concentration to evaluate aspects of consumption, combustion quality, behavior at low temperature, interaction between the fluid and the surface, and safety. The results showed that blends with, at least 1.0 per cent, by volume of additive and 20 per cent by volume of anhydrous ethanol are stable at temperatures above 10 degrees Celsius and respected most of the current Brazilian specifications for diesel fuel. Experimental tests on a compression ignition engine MWM 4.10 TCA (Euro III) were performed with these mixtures. The results showed that the diesel fuel substitution alters the characteristics of combustion: the increased ethanol content implied an increase of the ignition delay, a faster heat release and a decrease of maximum pressure. Despite these non-optimized conditions for injection and combustion, results showed a better conversion of ethanol chemical energy into brake power, in comparison to the values found in flex fuel spark ignition engine, in addition to a small increase in the indicated efficiency of the engine.
Luszcz, Pawel. "Combustion diagnostics in Homogeneous Charge Compression Ignition optical and thermal single cylinder engines". Thesis, University of Birmingham, 2009. http://etheses.bham.ac.uk//id/eprint/524/.
Texto completoFayad, Mohammed Ali. "Particulate Matter (PM) characteristics from compression ignition diesel engines operated by renewable fuels". Thesis, University of Birmingham, 2017. http://etheses.bham.ac.uk//id/eprint/7919/.
Texto completoScaringe, Robert J. (Robert Joseph). "Extension of the high load limit in the Homogeneous Charge Compression Ignition engine". Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/50585.
Texto completoIncludes bibliographical references (p. 120-121).
The Homogeneous Charge Compression Ignition (HCCI) engine offers diesel-like efficiency with very low soot and NOx emissions. In a HCCI engine, a premixed charge of air, fuel and burned gas is compressed to achieve autoigntion. Combustion occurs throughout the chamber volume resulting in short overall burn duration. This short burn duration can cause excessively high pressure rise rates which lead to unacceptable engine noise and potentially reduced engine life. To combat this high pressure rise rate the engine must be operating with significant diluent, either excess air or burned exhaust gas. However this high level of dilution limits the specific output of the HCCI engine to levels far below spark ignition or diesel engines. The high load limit is a major challenge for the HCCI engine. This study utilized a single cylinder research to examine the high load limit and possible methods to extend it. The details of the high load limit were first explored across a range of intake temperatures, boost pressures, trapped residual fractions, equivalence ratios and external EGR ratios for a gasoline fueled HCCI engine. A significant finding was that the high load limit always occurs at the misfire limit and that for a given pressure rise rate constraint, the high load limit occurs at lowest possible intake pressure and trapped residual fraction needed to prevent misfire. A possible means to allow operation at higher boost pressures is to utilize cooled external EGR or to reduce the intake temperature. For a given burn fraction, increasing the EGR rate or reducing the intake temperature provided reduced MPRR.
(cont.) However with these changes, the misfire limit also shifted such that the value of the maximum load does not materially change. Thus boosting coupled with EGR or intake temperature reduction can not be used to significantly extend the high load limit. A correlation was developed for the burn duration. Multi-zone combustion simulations were used to confirm the form of this correlation. The multi-zone based correlations were then used to quantitatively examine the potential of thermal stratification as a means to extend the high load limit. It was shown that for a doubling of the width of the in-cylinder temperature distribution, a 30% increase in the high load limit is possible.
by Robert J. Scaringe.
Ph.D.
Johns, R. A. "The analysis of the combustion of methanol in lean-burning, high-compression engines using an engine combustion model". Thesis, University of Surrey, 1985. http://epubs.surrey.ac.uk/847267/.
Texto completoThoo, Wei Jet. "A study of the ignition delay characteristics of combustion in a compression ignition engine operating on blended mixtures of diesel and gasoline". Thesis, University of Nottingham, 2016. http://eprints.nottingham.ac.uk/32843/.
Texto completoBhari, Anil. "A Rapid Compression Machine with the Novel Concept of Crevice Containment". University of Akron / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=akron1294677850.
Texto completoPaolucci, Lorenzo. "High efficiency low temperature combustion in compression ignition engines for automotive and aeronautical applications". Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019.
Buscar texto completoLaforet, Christopher A. "Combustion of natural gas with entrained diesel in a heavy-duty compression-ignition engine". Thesis, University of British Columbia, 2009. http://hdl.handle.net/2429/17010.
Texto completoKevric, Arman. "Combustion characteristics of a compression ignition engine running on biodiesel and gasoline blended fuels". Thesis, University of Nottingham, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.605993.
Texto completoPeucheret, Steven. "Exhaust gas reforming of natural gas to aid homogeneous charge compression ignition engine combustion". Thesis, University of Birmingham, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.420510.
Texto completoGUEDES, ANDREW DAVID MENDES. "EXPERIMENTAL STUDY ABOUT ETHANOL IMPACT IN DIESEL-BIODIESEL-ETHANOL BLENDS IN COMPRESSION IGNITION ENGINES". PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2017. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=30923@1.
Texto completoAGÊNCIA NACIONAL DE PETRÓLEO
Há algum tempo biocombustíveis renováveis são potenciais soluções sugeridas às questões de emissão de poluentes e dependência da sociedade aos derivados fósseis. Biodiesel e etanol são combustíveis comerciais renováveis candidatos à substituição das fontes fósseis, especialmente, em motores de ignição por compressão, os quais são tipicamente mais eficientes do que aqueles de ignição por centelha. Misturas ternárias de diesel, biodiesel e etanol formam estratégias de substituição parcial do diesel aplicáveis em motores de ignição por compressão sem a necessidade de grandes adaptações. Nesta dissertação realizaram-se avaliações experimentais em um motor multi-cilíndrico de ignição por compressão (MWM 4.10 TCA), abastecido com misturas de diesel, biodiesel (até 15 por cento em teor volumétrico) e etanol anidro (até 20 por cento em teor volumétrico). Cada mistura ternária é composta por diferentes proporções do álcool e sempre com a concentração volumétrica de 1 por cento de um aditivo estabilizador da mistura. Portanto, os testes associam substituições parciais do diesel por biocombustíveis a avaliações de desempenho do motor e da combustão das misturas, sob algumas condições de carga, regimes de rotação e instantes de injeção de combustível. Os testes realizados indicam que misturas com 20 por cento em volume de concentração de etanol experimentam inícios de combustão até 4,7 graus CA mais atrasados. Porém, a busca de instantes otimizados na injeção de combustível trouxe melhorias ao desempenho do motor, permitiu conversões energéticas mais vantajosas do etanol na ignição por compressão frente à ignição por centelha, além de minimizar efeitos do etanol em retardar o início da combustão.
Renewable biofuels have been proposed for a long time as an alternative to the issues concerned to pollutants emission and also society s liability to fossil fuels. Biodiesel and ethanol are renewable commercial fuel candidates for fossil fuels substitution, especially, in compression ignition engines, which are typically more efficient than the spark ignition ones. Diesel s partial replacement, such as the substitution by ternary blends formed by diesel, biodiesel and ethanol, is a strategy applicable to compression ignition engines without the need of further modifications. In this dissertation tests were run in a multi-cylinder compression ignition engine (MWM 4.10 TCA), fueled with diesel, biodiesel (up to 15 percent in volumetric content) and anhydrous ethanol (up to 20 percent in volumetric content) blends. Each mixture should be composed by different alcohol s proportions and always containing a 1 percent volumetric concentration of additive in order to ensure ternary s blend stability. Therefore, tests try to ally diesel s partial replacement by biofuels with engine performance and blends combustion assessment, under some combinations of load, engine speed and injection timing conditions. The tests performed indicate that the start of the combustion experienced up to 4.7 degrees CA postponements, when fueled with a 20 percent ethanol volumetric concentration blend. Still, optimized injection timing investigation brought improvements to engine performance, allowed better ethanol energetic conversions through compression ignition when compared to spark ignition and could also minimize delays caused by ethanol s presence in the beginning of the combustion.
Norouzi, Shahrouz. "Interaction of diesel type fuels and engine fuel system components in compression ignition engines". Thesis, University of Birmingham, 2014. http://etheses.bham.ac.uk//id/eprint/5369/.
Texto completoAndreae, Morgan M. (Morgan MacKenzie). "Effect of ambient conditions and fuel properties on homogeneous charge compression ignition engine operation". Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/35616.
Texto completoIncludes bibliographical references (p. 197-198).
Practical application of Homogeneous Charge Compression Ignition (HCCI) combustion must demonstrate robust responses to variations in environmental conditions. This work examines the impact of ambient conditions and fuel changes on HCCI engine operation, and evaluates cam phasing as a mechanism to compensate for these changes. Experiments were carried out on a modified 2.3 L 14 production engine, and HCCI operation was achieved by the use of residual trapping by negative valve overlap. The first phase of the project examined the impact of changes in intake air temperature and humidity on HCCI operation. Exhaust cam phasing was used to control load, and intake cam phasing was use to produce a change in combustion phasing. Cam timing control was largely able to compensate for changes in combustion due to changes in air temperature and humidity. Higher intake air temperature advanced combustion phasing and resulted in a 1 bar reduction of the net indicated mean effective pressure (NIMEP) at the high load limit for lower engine speeds. Intake air temperature did have more of an impact during lean operation. Higher intake air humidity delayed combustion phasing.
(cont.) During stoichiometric operation, this delay allowed a small extension (a few tenths of a bar in NIMEP) in the high load limit. During lean operation, the delay in combustion timing resulted in a reduction of the high load limit. The second phase of the project examined the impact of market fuel composition variations on HCCI operation. Twelve test fuels were created to vary the composition of 5 fuel properties: Research Octane Number (RON), Reid Vapor Pressure (RVP), olefin content, aromatic content, and ethanol content. The test fuels were blends of different commercial refinery streams and contained hundreds of different hydrocarbons to be representative market gasolines. Fuel type was found to have only a small impact on the HCCI operating range, and cam phasing was largely able to compensate for changes in fuel composition. The main effect of the different fuel composition appeared to be differences in ignition delay.
by Morgan M. Andreae.
Ph.D.
Korkmaz, Metin [Verfasser]. "Experimental Investigation of Advanced Low-Temperature Combustion Concepts for Compression Ignition Engines / Metin Korkmaz". Düren : Shaker, 2021. http://d-nb.info/1229779345/34.
Texto completoSchönborn, A. "Influence of the molecular structure of biofuels on combustion in a compression ignition engine". Thesis, University College London (University of London), 2009. http://discovery.ucl.ac.uk/18674/.
Texto completo