Tesis: "Gasoline"

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Munhoz, João Fernando Villarrubia Lopes [UNESP]. "Método alternativo para detecção de não conformidade em gasolina comercial brasileira do tipo C". Universidade Estadual Paulista (UNESP), 2013. http://hdl.handle.net/11449/97957.

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O Governo brasileiro intervia diretamente na comercialização de combustíveis até a década de 90. Com a abertura do mercado, pequenos revendedores sem contrato exclusivo com qualquer distribuidora, chamados de ‘bandeiras brancas’, surgiram no ambiente concorrencial. Com o propósito de assegurar a qualidade, a Agência Nacional do Petróleo, Gás Natural e Biocombustíveis, ANP, criou portarias especificando as características físico-químicas da gasolina comercial brasileira, tal como a Portaria nº 309. Com a crescente quantidade de informações, a diminuição do tempo de análise é uma necessidade. Uma técnica promissora é a cromatografia gasosa ultrarrápida, capaz de realizar uma corrida em poucos minutos, ou até mesmo em alguns segundos. Para isso, o comprimento da coluna capilar e seu diâmetro interno são reduzidos e seu aquecimento é feito através de uma resistência encapsulada. Assim, é possível obter os mesmos resultados em tempo diminuído e com a mesma qualidade. O aumento do volume de informações obtido experimentalmente exige ferramentas matemáticas mais avançadas para seu tratamento. Desde a década de 70, a quimiometria tem sido aplicada na obtenção, representação e transformação destes dados. O objetivo deste trabalho é criar um método de cromatografia gasosa ultrarrápida para análise de gasolinas comerciais brasileiras e, com ferramentas quimiométricas, classificar quanto à qualidade segundo a ANP. No desenvolvimento, cerca de 580 amostras de gasolinas comerciais foram coletadas mensalmente na região centro-oeste do estado de São Paulo. Os ensaios físico-químicos obtidos revelaram que grande parte não estava em conformidade com as portarias estabelecidas, possuindo apenas um parâmetro em discordância: a quantidade de etanol em sua composição...
The Brazilian government intervened directly in the commercialization of fuel until de 90s. By opening of the marketing, small dealers without exclusive contract with any distributor, called ‘white flags’, appeared in the competitive environment. In order to ensure quality, the National Agency of Petroleum, Natural Gas and Biofuels, ANP, has created ordinances which specify physico-chemicals characteristics of Brazilian commercial gasoline, such as the Ordinance No 309. By increasing the amount of information, reducing the analysis time is a necessity. A promising technique is the ultra-fast gas chromatography, able to perform a chromatographic run in just few minutes, or even in seconds. Thereunto, the capillary column length and its internal diameter are reduced and its heating is done via an encapsulated resistor. It is possible to obtain the same results in reduced time and with the same quality. The increasing volume of information obtained experimentally requires more advanced mathematical tools for their treatment. Since the 70s, Chemometrics has been applied in acquisition, representation and processing these data. The objective of this work is to create an ultrafast gas chromatography method for analisys of the Brazilian commercial gasoline and, with chemometric tools, sort by their quality according to ANP. In development, about 580 commercial gasoline samples were collected monthly in the central-western state of São Paulo. The physico-chemical assays reveled that a great fraction of which was not in accordance with the ordinances established, having only one parameter in disagreement: the amount of ethanol in its composition. The addition of adulterants to some samples was necessary to increase the variability of the data. Monthly, 50 of 580 samples were selected by the hierarchical cluster analysis... (Complete abstract click electronic access below)

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2

Munhoz, João Fernando Villarrubia Lopes. "Método alternativo para detecção de não conformidade em gasolina comercial brasileira do tipo C /". Araraquara, 2013. http://hdl.handle.net/11449/97957.

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Orientador: José Eduardo de Oliveira
Coorientador: Danilo Luiz Flumignan
Banca: Aristeu Gomes Tininis
Banca: Fabio da Silva Vinhado
Resumo: O Governo brasileiro intervia diretamente na comercialização de combustíveis até a década de 90. Com a abertura do mercado, pequenos revendedores sem contrato exclusivo com qualquer distribuidora, chamados de 'bandeiras brancas', surgiram no ambiente concorrencial. Com o propósito de assegurar a qualidade, a Agência Nacional do Petróleo, Gás Natural e Biocombustíveis, ANP, criou portarias especificando as características físico-químicas da gasolina comercial brasileira, tal como a Portaria nº 309. Com a crescente quantidade de informações, a diminuição do tempo de análise é uma necessidade. Uma técnica promissora é a cromatografia gasosa ultrarrápida, capaz de realizar uma corrida em poucos minutos, ou até mesmo em alguns segundos. Para isso, o comprimento da coluna capilar e seu diâmetro interno são reduzidos e seu aquecimento é feito através de uma resistência encapsulada. Assim, é possível obter os mesmos resultados em tempo diminuído e com a mesma qualidade. O aumento do volume de informações obtido experimentalmente exige ferramentas matemáticas mais avançadas para seu tratamento. Desde a década de 70, a quimiometria tem sido aplicada na obtenção, representação e transformação destes dados. O objetivo deste trabalho é criar um método de cromatografia gasosa ultrarrápida para análise de gasolinas comerciais brasileiras e, com ferramentas quimiométricas, classificar quanto à qualidade segundo a ANP. No desenvolvimento, cerca de 580 amostras de gasolinas comerciais foram coletadas mensalmente na região centro-oeste do estado de São Paulo. Os ensaios físico-químicos obtidos revelaram que grande parte não estava em conformidade com as portarias estabelecidas, possuindo apenas um parâmetro em discordância: a quantidade de etanol em sua composição... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The Brazilian government intervened directly in the commercialization of fuel until de 90s. By opening of the marketing, small dealers without exclusive contract with any distributor, called 'white flags', appeared in the competitive environment. In order to ensure quality, the National Agency of Petroleum, Natural Gas and Biofuels, ANP, has created ordinances which specify physico-chemicals characteristics of Brazilian commercial gasoline, such as the Ordinance No 309. By increasing the amount of information, reducing the analysis time is a necessity. A promising technique is the ultra-fast gas chromatography, able to perform a chromatographic run in just few minutes, or even in seconds. Thereunto, the capillary column length and its internal diameter are reduced and its heating is done via an encapsulated resistor. It is possible to obtain the same results in reduced time and with the same quality. The increasing volume of information obtained experimentally requires more advanced mathematical tools for their treatment. Since the 70s, Chemometrics has been applied in acquisition, representation and processing these data. The objective of this work is to create an ultrafast gas chromatography method for analisys of the Brazilian commercial gasoline and, with chemometric tools, sort by their quality according to ANP. In development, about 580 commercial gasoline samples were collected monthly in the central-western state of São Paulo. The physico-chemical assays reveled that a great fraction of which was not in accordance with the ordinances established, having only one parameter in disagreement: the amount of ethanol in its composition. The addition of adulterants to some samples was necessary to increase the variability of the data. Monthly, 50 of 580 samples were selected by the hierarchical cluster analysis... (Complete abstract click electronic access below)
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3

Allen, Chris. "Thicker than gasoline /". Available to subscribers only, 2007. http://proquest.umi.com/pqdweb?did=1328049391&sid=18&Fmt=2&clientId=1509&RQT=309&VName=PQD.

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Coelho, Sérgio Ricardo Cunha. "Estudo da viabilidade técnica da utilização da corrente de gasolina natural em unidades de processamento de gás natural". [s.n.], 2010. http://repositorio.unicamp.br/jspui/handle/REPOSIP/266849.

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Orientador: Flávio Vasconcelos da Silva
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química
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Resumo: O crescimento da disponibilidade de gás natural no Brasil nos últimos anos foi possível graças ao desenvolvimento de novos campos de petróleo e gás e a mobilização da Petrobras no sentido do aproveitamento do gás produzido. O "Plangás", plano de antecipação da produção de gás, possibilitou ao país alcançar segurança na oferta sem depender do recebimento de gás da Bolívia, no entanto sem prescindir deste. Com a construção de diversas plantas de processamento, o país agora importa menos GLP, tradicionalmente deficitário e consequentemente produz grandes quantidades de gasolina natural, ambos resultantes do processamento de gás natural. A gasolina natural (CS+) é tradicionalmente incorporada ao petróleo do campo produtor devido a sua pequena escala de produção. O Objetivo deste trabalho foi propor alternativas para a utilização da gasolina natural (C5+) dentro dos limites de uma UPGN. Foi realizada a caracterização do C5+ através das técnicas mais destacadas na literatura e através das diversas de mistura procurou-se a melhor formulação para compor gasolina tipo "A", usando-se outras correntes de processo corno elevadores de octanagern. Verificou-se a possibilidade do uso do C5+ como solvente e finalmente corno carga para unidades de produção de etileno e seus subprodutos derivados do craqueamento térmico a vapor. Constata-se o caráter parafínico do C5+ através da sua crornatografia, PONA, Kw e octanagem baixa. A destilação ASTM D-86 evidencia a semelhança do C5+ com a nafta leve de destilação, corrente normalmente usada como carga para unidades de craqueamento para obtenção de olefinas. A análise das propriedades do CS+ mostra a inviabilidade do seu emprego corno gasolina. Só é possível seu aproveitamento corno gasolina através de misturas com outras naftas, sendo que as naftas de polimerização e craqueamento que se mostraram mais promissoras para este fim. Solventes leves podem ser produzidos por destilação do C5+, destacando-se os solventes de borracha e de extração. O rendimento para obtenção de eteno usando-se o C5+ como carga nas unidades de pirólise térmica a vapor pode chegar a 32% em massa, superando o rendimento das correntes liquidas tradicionalmente usadas nestas unidades. A projeção de produção de C5+ nos próximos anos, devido principalmente aos projetos do Plangás e Pré-sal certamente despertará na indústria petrolífera um maior interesse no aproveitamento desta corrente de processo.
Abstract: The increasing availability of natural gas in Brazil in recent years was made possible by the development of new fields of oil and gas and Petrobras mobilization towards tapping the gas produced. The anticipation plan for the production of natural gas, "Plangás", enabled the country to achieve security without depending on the offer of receiving gas from Bolivia, but without ignoring it. With the construction of several processing plants, the country now imports less LPG, traditionally deficit, and consequently produces large quantities of natural gas, resulting from both natural gas processing. The natural gasoline (C5+) is traditionally incorporated into the oil producing field due to their small scale production. The goal of this study was to propose alternatives to the use of natural gasoline (C5 +) within the limits of a UPGN. We performed the characterization of the C5 + through the techniques most prominent in the literature and through the various mixing rules sought to make the best formulation for gasoline Type "A", using other process streams such as octane elevators. There was the possibility ofusing the C5 +as a solvent and finally how raw material to load units of ethylene and byproducts derived from thermal steam cracking. It shows the paraffin character of the C5 + through its chromatography, PONA, Kw and low octane. Distillation ASTM D-86 shows the similarity of the C5 + with the light naphtha distillation, current commonly used as raw material to load cracking units for obtaining olefins. An analysis of the properties of C5 + shows the impracticality o f its use as gasoline. It is only possible through its use as gasoline mixtures with other naphtha, and the naphtha cracking and polymerization that have proven most promising for this purpose. Light solvents can be produced by distillation of the C5 +, especially rubber solvents, and extraction solvents. The yield for production o f ethylene using the C5 + as raw material in units of thermal pyrolysis steam can reach 32% by mass, exceeding the current net income traditionally used in these units. The projected production of C5 + in the coming years, due mainly to Plangás project and Pre-salt project, will do the oil industry will certainly be interested in exploiting this process stream.
Mestrado
Sistemas de Processos Quimicos e Informatica
Mestre em Engenharia Química

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Silva, Jacqueline Pereira Figueiredo Ferreira da. "Caracterização de compostos aromáticos em gasolina comercial". Universidade do Estado do Rio de Janeiro, 2009. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=2833.

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A contaminação do ar e do meio ambiente por combustíveis derivados de petróleo tem sido objeto de crescente pesquisa no Brasil. Dentre os tipos de poluição ao meio ambiente, a poluição atmosférica é a que causa mais incômodo à população. Esta exerce efeitos sobre a saúde humana, causando desde simples irritações até câncer de pulmão. Dos poluentes mais perigosos encontrados nesses ambientes, são destaques os hidrocarbonetos e os compostos monoaromáticos como o benzeno, tolueno e xilenos (BTX), presentes nesses combustíveis, que são extremamente tóxicos à saúde humana. Para controle desses compostos orgânicos voláteis, é necessário quantificá-los e compará-los aos valores limites de tolerância legislados no Brasil. A utilização da técnica de cromatografia gasosa e da técnica de espectroscopia por infravermelho permite realizar essa tarefa de maneira relativamente simples e rápida. Portanto o objetivo deste trabalho foi apresentar a composição química de amostras de gasolina do tipo C comercializadas nos postos revendedores da Região Metropolitana do Estado do Rio de Janeiro. Foram feitas análises quantitativas dos principais grupos químicos (parafínicos, olefínicos, naftênicos e aromáticos) e etanol por Cromatografia Gasosa de Alta Resolução e da composição de benzeno, tolueno e xileno (BTX) pela técnica de absorção no infravermelho. Os resultados foram comparados com os limites dados pela especificação da ANP (Portaria n 309) para a qualidade da gasolina, com o objetivo de se verificar se estão em conformidade com este agente regulamentador. Os resultados mostraram que todos os teores encontrados de olefínicos e aromáticos foram abaixo do limite especificado. Alguns postos apresentaram os teores de benzeno acima do limite especificado, indicando um nível de ação por parte da ANP principalmente pela ação tóxica do benzeno
The air contamination and the environment by fuels derived from crude oil has been object of increasing research in Brazil. Amongst the types of pollution to the environment, the atmospheric pollution is the one that cause more discomfort to the population. This exerts effects on the human health, causing since simple irritations until lung cancer. Among the most dangerous pollutants found in these environments are prominences the aliphatic hydro carbons and monoaromatic hydrocarbons compounds as benzene, toluene and xylems (BTX), present in these fuels that are extremely toxic to the human health. To control these volatile organic compounds, is necessary to quantify and to compare them with the tolerance limits value legislated in Brazil. The gas chromatography and infra-red ray spectroscopy techniques utilization allows realizing easily and fast these tasks. Therefore the objective of this work was to present the type C gasoline samples chemical composition commercialized on the gas station of the metropolitan region on Rio de Janeiro state. Had been made quantitative analyses for the main chemical groups (paraffins, olefins, naphthenics and aromatics) and ethanol by high resolution Gas Chromatography and the composition for benzene, toluene and xylem (BTX), by infra-red ray absorption technique. The results had been compared with the limits given by ANP specification (Portaria n 309) for the gasoline quality, with the objective to verify if they are in compliance with this regulatory agent. The results had shown that all amount founded for aromatics and olefinics had been below of the specified limit. Some gas station had presented amount for benzene above of the specified limit, indicating that ANP need to take some actions toward these gas station, mainly for the benzene toxicity action

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Bueno, Aerenton Ferreira. "Desenvolvimento de um analisador de processo por espectroscopia no infravermelho próximo (NIR) para previsão de propriedades de derivados de petróleo". [s.n.], 2011. http://repositorio.unicamp.br/jspui/handle/REPOSIP/249976.

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Orientador: Célio Pasquini
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química
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Resumo: O trabalho trata do desenvolvimento de um analisador de processo utilizando a espectroscopia no infravermelho próximo (NIR) para prever propriedades de derivados de petróleo, como gasolina e querosene de aviação. O instrumento foi projetado para ser instalado diretamente em uma linha de processo numa unidade industrial, realizando, de maneira automatizada, a coleta, análise e descarte da amostra, envio dos resultados obtidos, além de operações como limpeza da célula e diagnósticos funcionais. Um protótipo de um espectrofotômetro NIR de bancada foi construído, a partir do qual, foi montado um espectrofotômetro de laboratório plenamente funcional. O espectrofotômetro foi instalado num gabinete com sistema de pressurização (para estar de acordo com a classificação da área industrial), controlador de temperatura e dispositivos para a seleção da amostra e limpeza da célula, tornando-se, assim, um analisador de processo. Um programa de computador em linguagem Visual Basic foi desenvolvido para a operação automatizada do analisador. Foram obtidos espectros e desenvolvidos modelos de calibração multivariados para prever uma série de parâmetros de qualidade de gasolina (como destilação, octanagem e concentrações de aromáticos, olefinas e saturados) e querosene de aviação (massa específica e ponto de congelamento), que apresentaram resultados compatíveis com os valores de precisão dos métodos de referência utilizados. O analisador foi instalado num sistema de mistura para produção de gasolina de uma refinaria de petróleo, visando prever, em tempo real, vários parâmetros de qualidade desse produto, para a otimização do processo produtivo
Abstract: The work deals with the development of a process analyzer using near infrared spectroscopy (NIR) to predict properties of petroleum products like gasoline and jet fuel. The instrument was designed to be mounted directly on a line in an industrial process, performing automatically the collection, analysis and disposal of the sample, transmission of results, as well as operations such as cleaning the cell and functional diagnosis. A prototype of a benchtop NIR spectrometer was built, from which a fully functional laboratory spectrophotometer was assembled. The spectrophotometer was installed in a cabinet with a pressurization system (to be consistent with the classification of the industrial area), temperature controller and devices for sample selection and cleaning of the cell, becoming thus a process analyzer. A computer program written in Visual Basic was developed for the automated operation of the analyzer. Spectra were acquired and multivariate calibration models were developed to predict a series of gasoline (such as distillation, octane and concentrations of aromatics, olefins and saturated) and jet fuel quality parameters (specific gravity and freezing point), who presented results compatible with the precision values of the reference methods used. The analyzer was installed in a blending system for production of gasoline in an oil refinery, aimed to provide, in real time, various quality parameters of the product, to optimize the production process
Doutorado
Quimica Analitica
Doutor em Ciências

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Varzacacou, Nicolas do Nascimento. "Interação de gasolina, benzeno, tolueno e xilenos com argilominerais esmectíticos da Formação Resende, Bacia de São Paulo". Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/44/44142/tde-08092009-155727/.

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Dados da CETESB revelam que a comercialização de derivados do petróleo na Cidade de São Paulo, em especial a gasolina, tem gerado um número significativo de casos de vazamento de combustíveis, causados pela falta de manutenção de equipamentos, deterioração de tanques e tubulações, e falhas operacionais decorrentes do despreparo dos profissionais que atuam nesses estabelecimentos. A área urbana da Cidade de São Paulo está, em grande parte, edificada sobre os depósitos sedimentares de idade cenozóica da Bacia de São Paulo, onde a Formação Resende apresenta distribuição generalizada e compreende mais de 80% do preenchimento sedimentar. Argilominerais esmectíticos predominam na fração fina dos sedimentos da Formação Resende e a possível interação deles com hidrocarbonetos foi o objeto de investigação dessa dissertação. Nesse sentido, o presente trabalho teve por objetivo o estudo laboratorial da interação, por meio de sorção e desorção, de hidrocarbonetos encontrados comumente, como gasolina comercial, benzeno, tolueno e xilenos, com argilominerais esmectíticos da Formação Resende, no contexto da zona vadosa, na Bacia de São Paulo. Para tanto, três amostras argilosas da Formação Resende foram coletadas na zona leste da Cidade de São Paulo, tendo sido efetuada sua caracterização granulométrica, mineralógica (via DRX) e química (análise de CNH). Em testes de inchamento com gasolina e orgânicos puros, nenhuma das amostras apresentou absorção dos compostos. Os testes de adsorção e desorção procuraram caracterizar a interação dos hidrocarbonetos com a rocha total, fração silte e fração argila dos sedimentos, variandose o tempo de exposição (30 minutos a 32 dias) das amostras aos contaminantes. Os resultados obtidos permitiram reconhecer que a adsorção é o mecanismo de sorbância predominante. A variação das concentrações ao longo do tempo evidenciou que a interação amostra/contaminante é dinâmica ao longo do tempo de contato, havendo momentos distintos de sorbância, com variação significativa e bem representada dos teores adsorvidos, e que essas fases ocorrem independentemente da granulometria ou mineralogia das amostras, sendo: os sedimentos argilosos adsorvem, na média, as mesmas ordens de grandeza de cada contaminante, o que é devido a sua homogeneidade granulométrica e mineralógica em pequena escala; dentro da ordem de grandeza de adsorção de cada contaminante, as diferenças composicionais (granulométricas e mineralógicas) entre as amostras de sedimentos argilosos alteram os teores dos compostos em função da proporção de argila na rocha total, de forma que quanto mais contaminante será adsorvido, e do tipo de argilomineral predominante na fração argila, sendo a maior proporção de esmectita um fator favorável.
Data from the Environmental Agency of São Paulo State (Company of Environmental Sanitation Technology CETESB) reveal that the commercialization of petroleum products in the city, especially gasoline, has generated a high number of fuel leakages and contaminated areas. The urban area of São Paulo city is underlain by the Cenozoic sedimentary deposits of the São Paulo Basin. In this basin, smectiterich mudstone of the Resende Formation is widely distributed and comprises over 80% of the sedimentary filling. The aim of this study was to investigate the interaction of smectiterich mudstone of the Resende Formation with hydrocarbons in the São Paulo Basin. The sorption and desorption of common hydrocarbons, such as gasoline, benzene, toluene and xylene, by the smectitic clay minerals, in the context of vadose zone, were investigated in laboratory. Three representative subsurface samples of mudstone were collected in the east part of São Paulo city and characterized by granulometry, Xray analysis and CHN determination. Swelling test with gasoline and pure organic compounds does not promote absorption in the three studied samples. Adsorption and desorption tests were employed to characterize the interaction between the hydrocarbons and the wholerock, silt and clayfractions of the mudstone in different time intervals of contact (30 minutes to 32 days). The results revealed the adsorption as the main interaction mechanism. Variations in concentration of contaminants in different time intervals of contact indicated a dynamic interaction between sample and hydrocarbons, existing phases with distinct amounts of organics adsorbed (or retained after desorption). Theses phases are controlled by the time of contact and are independent of samples granulometry and mineralogy, and contaminant type. The three mudstone samples adsorb about the same amount of each contaminant, which is due to their overall granulometric and mineralogic homogeneity. Nevertheless, minor and local changes in sample composition (granulometry and mineralogy) cause a small scale variation in the amounts of each contaminant adsorbed as a result either of clay proportion in the whole-rock and of the predominant clay mineral in the clay fraction.

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Diehl, Daiane. "Formação do preço de etanol hidratado no Estado de São Paulo e sua relação com os mercados de açúcar e de gasolina". Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/11/11132/tde-14082012-094235/.

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O principal objetivo deste estudo foi estimar um modelo analítico que explicasse a relação entre os mercados de etanol hidratado e de gasolina C, incluindo, também, efeitos de outros fatores, como o preço de açúcar nos mercados doméstico e internacional e a renda. Por sua capacidade de captar efeitos dinâmicos, utilizou-se o Modelo de Auto-Regressão Vetorial com Correção de Erro VEC. A análise das funções de demanda dos combustíveis mostrou que o consumo de etanol responde de forma expressiva a variações contemporâneas no próprio preço e no preço da gasolina, produto substituto nesse segmento de mercado. Já com relação à demanda de gasolina C, verifica-se que suas vendas respondem menos tanto ao próprio preço como ao do etanol. De maneira geral, a análise das funções de respostas a impulsos permite verificar que os efeitos dos choques não antecipados sobre as variáveis do modelo são de curta duração, desaparecendo, na maior parte das vezes, após o terceiro mês. A renda mostrou-se importante variável explicativa tanto para o consumo de etanol hidratado quanto de gasolina C. Um choque exógeno no preço internacional de açúcar resulta em um efeito elevado no preço do produto no mercado doméstico. De outro lado, um choque no preço doméstico de açúcar tem impacto significativo no preço do etanol anidro (elasticidade acumulada de 0,57), sendo que esses produtos concorrem pela mesma matéria-prima na indústria. Como este preço, por sua vez, representa uma variável proxy para o preço do etanol hidratado no segmento produtor, pode-se afirmar que 60% das variações de preço neste segmento são transmitidas ao preço do combustível no mercado varejista. A análise da decomposição das variâncias do erro de previsão evidenciou que a variável que tem maior impacto sobre o preço do etanol hidratado combustível no varejo é o preço do etanol anidro (proxy do preço do etanol hidratado no segmento produtor). Os principais determinantes da venda de etanol hidratado no varejo são a renda, o preço do etanol hidratado combustível no varejo e o do etanol anidro no segmento produtor. Já com relação às vendas de gasolina C no varejo, o principal determinante é a renda, enquanto as demais variáveis pouco contribuem para explicar suas variações. Finalmente, a análise da previsão dentro da amostra para o preço do etanol hidratado no segmento varejista sugere que este preço assumiria um patamar mais elevado, não fosse a atual política de controle de preços dos derivados do petróleo adotada no Brasil. Nas duas últimas safras do período estudado, o preço praticado está, em média, 23,7% abaixo do previsto pelo modelo estimado neste estudo. Vale ressaltar que o modelo estimado capta o padrão médio do comportamento da série, dados os fundamentos de mercado considerados, os quais explicam pelo menos 76% das variações do preço do etanol hidratado no varejo.
The main objective of this study was to estimate an analytical model to explain the relationship between the markets of hydrated ethanol fuel and gasoline C, including effects of other factors such as sugar prices in the domestic and the International markets and income. Because of its ability to capture dynamic effects, the Auto-regression Model with Vector Error Correction VEC was used. Analysis of the demand function showed ethanol fuel consumption significantly responds to contemporary variations of its price and gasoline price, replacement product in this market segment. Regarding the demand for gasoline C, it appears that sales respond less to its price and ethanol price. In general, analysis of the response functions to impulses allows to verify that the effect of unanticipated shocks on model variables are of short duration and disappears, in most cases, after three months. Income proved to be important in ethanol and gasoline C consumption. An exogenous shock in the international sugar price results in a large effect on the product price in the domestic market. Therefore, a shock in the domestic sugar price has a significant impact on the anhydrous ethanol price (accumulated elasticity of 0.57), once these products compete for raw material in the sector. Given that this price represents a proxy variable for the hydrous ethanol price for the industry, 60% of the price in this segment is transmitted to the fuel price in the retail market. A decomposition analysis of forecast error variance showed that the variable with greater impact on the hydrated ethanol fuel price in the retail market is the anhydrous ethanol price (proxy of the hydrated ethanol price in the industry). The main determinants of hydrated ethanol sales in the retail market are the income, the hydrated ethanol fuel price and the anhydrous ethanol fuel price in the industry. Gasoline C sales in the retail market are mostly determined by income, while the other variables contribute little to explain its variations. Finally, the analysis of the in-sample forecast for the hydrated ethanol price in the retail market suggests that this price would assume a higher level, if there were not the current policy of controlling prices of petroleum derivatives adopted in Brazil. In the last two seasons of the analysis, the price was on average 23.7% below that predicted by the model estimated in this study. It is noteworthy that the estimated model captures the average standard of the series, given the market fundaments considered, which explain at least 76% of the variations in the hydrated ethanol price in the retail market.

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9

Ferreira, Silvia Maria. ""Relação entre a espessura real e aparente da gasolina com etanol e da gasolina pura em colunas de laboratório"". Universidade de São Paulo, 2003. http://www.teses.usp.br/teses/disponiveis/44/44133/tde-26062005-171404/.

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A gasolina que é comercializada no Brasil sofre a adição de álcool etílico anidro, também conhecido como etanol, em frações que podem variar de 20 a 24%. O uso desse composto adicionado à gasolina serve para aumentar a octanagem e reduzir a emissão de monóxido de carbono para a atmosfera. Esta pesquisa teve como objetivo verificar e comparar a relação existente entre a espessura encontrada nos poços de monitoramento e no meio poroso, tanto para gasolina pura quanto para a gasolina com 20 % de etanol (E-20), após a simulação de um vazamento em subsuperfície, utilizando colunas de areia em laboratório, visto que esta relação é de extrema importância para o cálculo preciso do volume do contaminante a ser bombeado, no caso de vazamentos de combustível. As colunas foram confeccionadas utilizando-se 2 tubos de acrílico transparente com 100 cm de comprimento e 23cm de diâmetro interno que foram fixados a uma base de acrílico transparente com 0,60 cm de espessura. Um tubo de PVC branco com 100 cm de comprimento e 3,50 cm de diâmetro interno, com ranhuras horizontais de 0,10 cm de largura foi cortado longitudinalmente e cada metade foi fixada nas paredes dos tubos de acrílico para representar o poço de monitoramento. As colunas foram preenchidas com areia de granulometria muito fina (0,088 mm). Os resultados obtidos mostraram que a espessura aparente da gasolina pura foi 2,6 vezes superior à espessura real da fase livre e a espessura aparente da E-20 foi 0,6 vezes superior a espessura real da fase livre. A tensão interfacial da E-20 foi 67% inferior à tensão interfacial da gasolina pura, possibilitando que uma quantidade maior de poros fosse acessada, refletindo em valores de saturação total 54% superiores ao da gasolina pura. Parte da fase gasolina da E-20 deve ter sido depositada como glóbulos desconectados nos poros caracterizando uma saturação residual, devido ao particionamento preferencial do etanol para a água subterrânea e o conseqüente enriquecimento em gasolina na fase gasolina. Esta saturação residual deve ter dificultado o fluxo e consequentemente reduzido a permeabilidade relativa para a fase aquosa, causando o retardamento da chegada da E-20 no poço de monitoramento.
Commercial gasolines sold in Brazil are added ethanol from 20 to 24% by volume. This oxygenated additive raises the octane level and reduces carbon monoxide emissions to the atmosphere. Underground storage tanks and gasoline lines are a major potential problem for soil and groundwater contamination. Since ethanol has cosolvent properties that alter the behavior of phase distribution in subsurface, this research compares the existing relationship of apparent and actual thicknesses of free phase gasoline and E-20 (80% gasoline and 20% ethanol by volume) found respectively in monitoring wells and medium porous material using two column experiments. Two cylindrical plexiglass columns were used (100 cm long and 23 cm in internal diameter). The bottom ends were capped using two 35 x 35 cm plexiglass plates. A spout-like connection of PVC was fitted near the base of each column as an inlet/outlet end. One well screen (100 cm long and 3,5 cm in internal diameter) in white PVC was cut in half lengthwise and attached to the inside walls of columns to be used as monitoring wells. The columns were then filled with 0,088 mm grain size sand (very fine).The apparent thickness of pure gasoline was 2.6 times thicker than the actual thickness in the aquifer while it was only 0.6 thicker for E-20. The interfacial tension of E-20 is 67% lower than the that of the pure gasoline, allowing a larger quantity of pores to be accessed, which was reflected in an oil saturation 54% higher than that of pure gasoline. Part of the gasoline phase of E-20 must have been precipitated as disconnected doplets within the pores creating a residual saturation and consequently reducing the permeability with respect to the aqueous phase delaying the breakthrough of E-20 in the monitoring well.

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10

Eckert, Andrew. "A study of Canadian retail gasoline prices". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape7/PQDD_0016/NQ46340.pdf.

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Danping, Wei. "The lubricity of gasoline fuels". Thesis, Imperial College London, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.299833.

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Yates, Andrew David Bennett. "Abnormal combustion - methanol versus gasoline". Doctoral thesis, University of Cape Town, 1988. http://hdl.handle.net/11427/8386.

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Includes bibliographical references.
The maximum efficiency of conventional gasoline engines is largely determined by the compression ratio, and this is limited by the onset of kno8k. The maximum cylinder size is similarly constrained. The relatively higher knock resistance of methanol opens up possibilities for increased efficiency or engine size. The auto-ignition of methanol and gasoline was characterised in terms of fundamental parameters and the results were compared. The research findings were used in the analysis of a particular combustion chamber design to assess the potential of using squish as a means of avoiding knock in a large, spark-ignition methanol engine.

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Al-Bassir, Soleman A. "Hedonic analysis of gasoline retailing". PDXScholar, 1988. https://pdxscholar.library.pdx.edu/open_access_etds/1214.

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Researchers have difficulty modeling the influence of retailing attributes on consumer choice. The literature of retailing that has dealt with this issue has conventionally used experimental data for estimating the influence of retailing attributes on consumer behavior. The present research applies hedonic analysis to the measurement of the value of retailing attributes. This is accomplished by applying hedonic specifications to supply and demand models for the retail sales of unleaded gasoline for the purpose of estimating the influence of specified retailing attributes on retail prices. Four retailing attributes-accessibility, convenience, service, and competition-were expected to have a determinable value that was measurable through hedonic specifications. Spatial competition was expected to influence retail prices by lowering them. The value of retailing attributes was expected to be variable relative to household income. It was found that the value of the specified retailing attributes could be isolated and determined. The application of hedonic analysis to the supply and demand of unleaded gasoline provided a relatively precise and consistent market value, which was represented by the "ask" and "bid" implicit prices of these retailing attributes. Spatial competition was seen to exert an important influence on retailing, tending to lower retail prices. The value of retailing attributes was found to be variable relative to household income. The relative consistency and precision of hedonic analysis in the measurement of the value of retailing attribute was reinforced insofar as the findings were consistent with generally accepted notions of retail marketing and consumer behavior as represented in the literature in the field.

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14

McNay, Aaron David. "An estimation of the demand for gasoline in Montana, and projections of future gasoline consumption". Thesis, Montana State University, 2008. http://etd.lib.montana.edu/etd/2008/mcnay/McNayA0808.pdf.

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How gasoline consumption responds to changes in its own price is of interest to many different groups. States fund a large portion of their road construction and maintenance by a direct tax on gasoline. The federal government also receives revenue by directly taxing gasoline. Automobile manufacturers are interested in how consumers\' demand for fuel efficiency changes with changes in the price of gasoline. For these reasons, and more, it is important to understand how gasoline consumption will respond to changes in price. Other researchers have already attempted to measure gasoline demand at the national level. However, very little work has been done at a state level. This thesis attempts to apply a model similar to the previously developed national models at a state level. The state examined here is Montana. This state is of particular interest because it differs from the national average in several key characteristics, including more vehicles per capita, less fuel efficient vehicles, and few alternatives to driving such as public transportation. The model employed simultaneously estimates the demands for vehicle miles traveled and fuel efficiency. By estimating the demands for both of these variables, it is possible to indirectly determine the demand for gasoline. When estimated, it appears that Montana\'s consumption of gasoline is less responsive to changes in gasoline prices, and more responsive to income changes, than the nation as a whole. The estimated model is used to project future gasoline consumption. The projections were developed using potential future levels of income, population, and gasoline prices. These projections indicate that it would require gasoline prices rising considerably before per capita consumption would decline.

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15

FILHO, GUILHERME BARROS DE CASTRO. "FLUX AND TRANSPORT STUDY OF PURE GASOLINE AND GASOLINE BLENDED ETHANOL IN UNSATURATED POROUS MEDIA". PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2007. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=11332@1.

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CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO
O derramamento no solo de poluentes imiscíveis com a água (NAPLs) devido a vazamentos de tanques de armazenamento ou dutos e acidentes de transporte é de grande interesse, pois o NAPL e/ou seus constituintes podem migrar através da zona vadosa até atingir o lençol freático e contaminar as fontes de água potável. No Brasil, a maioria dos postos de combustível e terminais de armazenamento possui tanques de etanol, gasolina misturada com etanol e óleo diesel. Um eventual derramamento ou vazamento de hidrocarbonetos derivados de petróleo, conhecidos como LNAPL, misturados com etanol tem um maior potencial de contaminação em função do efeito de co- solvência. A motivação deste trabalho é que muitos estudos têm sido realizados com principal interesse na zona saturada e pouco se sabe sobre o comportamento destes contaminantes na zona não saturada (McDowell e Powers, 2003 e Österreicher et al., 2007). Portanto, foram realizados ensaios de coluna com esferas de vidro com o objetivo de simular os vazamentos de hidrocarbonetos líquidos na superfície e comparar a massa de benzeno que fica retida no meio poroso em um vazamento de gasolina pura ou com etanol. Para avaliar estes ensaios em uma dimensão foi utilizado um programa disponível no sítio da Agência de Proteção Ambiental dos Estados Unidos (EPA) chamado Hydrocarbon Spill Screening Model (Weaver et al., 1994) e implementado um modelo para efetuar o balanço de massa e considerar o efeito de co-solvência em função da adição de etanol na gasolina comercial brasileira. Os resultados dos ensaios de laboratório foram comparados com os obtidos através do modelo supracitado e apresentaram uma aproximação satisfatória da previsão do comportamento do contaminante.
The subsurface release of water immiscible pollutants (NAPLs) due to leaks in storage tanks or pipelines and spilling transportation accidents is of great concern, since the NAPL or its constituents may migrate through the vadose zone until reaching the water table and eventually contaminate clean water sources. In Brazil, most of the gas stations store ethanol, pure and gasoline blended ethanol, diesel, among others in tanks. A spill or leak of petroleum hydrocarbons, known as LNAPL (light Nonaqueous phase liquid), combined with ethanol has a major contamination potential associated to cosolvency effects. The motivation of this work is that many studies have been developed with special interest in the saturated zone and little is known about the behavior of these pollutants in the vadose zone (McDowell e Powers, 2003 e Österreicher et al., 2007). Thus, one dimensional column tests were performed in a glass porous media to simulate the spill of hydrocarbons in the subsurface and compare the retained mass of benzene in the porous media after a release of a pure or ethanol blended gasoline. In order to evaluate these 1D tests results, the Hydrocarbon Spill Screening Model - HSSM (Weaver et al., 1994) was used. This program can be found in the Environmental Protection Agency (EPA) website. A model was also implemented to consider the cosolvency effects in function of the ethanol addition in Brazilian`s commercial gasoline. The laboratory`s results were compared with the ones obtained by the model mentioned above and showed a satisfactory approximation for the prediction of the contaminant behavior.

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16

Muehlegger, Erich J. "Essays on gasoline price spikes, environmental regulation of gasoline content, and incentives for refinery operation". Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/32402.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Economics, 2005.
Includes bibliographical references (p. 145-153).
Since 1999, regional retail and wholesale gasoline markets in the United States have experienced significant price volatility, both intertemporally and across geographic markets. In particular, gasoline prices in California, Illinois and Wisconsin have spiked occasionally well above gasoline prices in nearby states. The three chapters of my thesis study the relationship between gasoline price spikes, environmental regulation of gasoline content, unanticipated refinery outages and other recent structural changes in the domestic oil market. In the first chapter, I detail current regulations related to gasoline content. Implemented regionally to address local mobile-source emissions, gasoline content regulations increase costs to refiners, transporters and distributors of gasoline, as well as reduce the fungibility of gasoline across different regions. Chapter one provides a summary of the regulations and a qualitative description the costs the regulations impose on refiners, transporters and distributors of gasoline. In chapter two, I estimate two distinct effects of gasoline content regulations in California, Illinois and Wisconsin: (i) the effect of increased production costs due to supplementary regulation, and (ii) the effect of incompatibility between these blends and gasoline meeting federal reformulated gasoline standards. Using a structural model based on the production optimization problem of refiners, I simulate wholesale prices for jet fuel, diesel and four blends of gasoline in each geographic market. I then specify a counterfactual in which gasoline in the three states met federal requirements.
(cont.) Using a similar methodology, I also estimate the effect of two structural changes in the domestic oil market, (i) changes in refinery ownership and (ii) limited expansion of domestic refining capacity. I estimate the effect of increased refining costs is 4.5, 3.0 and 2.9 cents per gallon in California, Illinois and Wisconsin. The effect of incompatibility with federal RFG criteria, conditional on an in-state refinery outage, is 4.8, 6.6 and 7.1 cents per gallon in California, Illinois and Wisconsin. Controlling for the magnitude of local outages in these areas, I estimate that 72, 92 and 91 percent of price spikes created by local refinery outages could be mitigated by compatibility with federal RFG standards. In chapter three I study the challenge faced by regulators of differentiating strategic withholding of capacity from unreliable production. If a regulator cannot verify "unplanned" outages, the regulator cannot credibly distinguish between strategic behavior by producers and unlucky realizations of facility reliability. I specify a model in which a firm's choices of production and maintenance affect facility reliability and study how incentives arising from ownership of more than one facility affect facility reliability. I then statistically test whether the pattern of incidents is consistent with the predictions of the theoretical model. I find statistically significant evidence that ownership of other local refining capacity is correlated with the probability of an outage at a given refinery. In addition, the relationship between ownership and incident likelihood is greatest for markets with special gasoline formulations, where a refinery outage has the largest effect of gasoline prices. In these markets, expected incident likelihood is 30 percent greater for a refinery affiliated with another refinery that it is for an unaffiliated refinery.
by Erich Johann Muehlegger.
Ph.D.

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17

Snelling, Jeff Barnett Mark O. "Higher ethers as replacement oxygenates for methyl tertiary butyl ether in gasoline synthetic and environmental aspects /". Auburn, Ala., 2007. http://repo.lib.auburn.edu/2006%20Fall/Dissertations/SNELLING_JEFF_42.pdf.

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18

Sauer, William. "Fuel excise taxes and consumer gasoline demand comparing average retail price effects and gasoline tax effects /". CONNECT TO ELECTRONIC THESIS, 2007. http://dspace.wrlc.org/handle/1961/4136.

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19

Li, Haiying. "CFD modelling study of sprays and combustion of gasoline and DMF in direct injection gasoline engines". Thesis, University of Birmingham, 2013. http://etheses.bham.ac.uk//id/eprint/4491/.

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The new biofuel candidate, 2, 5-Dimethylfuran (DMF) has received increasing interest as a potential alternative to fossil fuels, owing to the recent development of its new production technology. However, the effect of DMF properties on the fuel spray and vaporization, subsequent combustion processes and emission formation in the current Gasoline Direct Injection (GDI) engine is still not well understood. To investigate spray and combustion characteristics of DMF and explore possible applications to the IC engines, a three-dimensional Computational Fluid Dynamics (CFD) model has been developed using the KIVA3V code with improved spray models (nozzle flow model, spray atomization and secondary breakup models) and combustion models. This CFD model was validated by the optical diagnostics and then applied to study the in-cylinder mixture preparation and combustion characteristics of DMF in a GDI engine. The mixture preparation analysis shows both insufficient mixing time and significant spray-wall interaction when DMF is used result in relatively poor air/fuel distributions. Compared to the nearly homogeneous mixture with the gasoline fuel spray, a very rich fuel-air mixture of 7.7% and extremely lean mixture of 4.7% of the total charge has been observed in the case of DMF at the end of compression stoke. The analysis of combustion characteristics compared with the case of gasoline show that slightly longer combustion duration of DMF results from its lower laminar flame speed. The higher anti-knocking quality of DMF makes more advanced spark timing possible which brings about higher peak pressure and temperature and higher IMEP.

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20

Chapman, Jacqueline Louise. "Combustion derived deposits in gasoline engines". Thesis, Imperial College London, 1991. http://hdl.handle.net/10044/1/46708.

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21

Praharso, Praharso School of Chemical Engineering &amp Industrial Chemistry UNSW. "The autothermal reforming of artificial gasoline". Awarded by:University of New South Wales. School of Chemical Engineering and Industrial Chemistry, 2003. http://handle.unsw.edu.au/1959.4/19294.

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Stringent legislation on control of vehicle exhaust emissions has led to consideration of alternative means of reducing emissions, with hydrogen fuel cell powered vehicles being accepted as one favoured possibility. However, the difficulties of storing and distributing hydrogen as a fuel are such that the conversion of more readily available fuels to hydrogen on board the vehicle may be required. The production of hydrogen by the partial oxidation of isooctane over Rh/Al2O3, Rh/CeO2-?l2O3 and Rh/CeO2-ZrO2 catalysts has been investigated. Oxidation was initiated at temperatures between 200 ?220 oC. The yield of hydrogen was 100%. CeO2-ZrO2 was found to be the best support. The production of hydrogen by the autothermal reforming of artificial gasoline has been studied. Part of gasoline is oxidised to produce heat and steam to promote the steam reforming of unburnt gasoline to produce hydrogen. The use of platinum impregnated on ceria supports (active for oxidation) and a commercial nickel based catalyst (Ni-com), for steam reforming of gasoline have been explored. Initiation of oxidation of artificial gasoline over unreduced platinum based catalysts occurred at temperature as low as 150 oC, depending on the oxygen:carbon ratio and the liquid hydrocarbon used. Detailed kinetic studies of the steam reforming of isooctane and artificial gasoline (a mix of cyclohexane, isooctane and octane) over pre-reduced Ni-com catalysts showed that the reaction was 0.17 order in isooctane and 0.54 order in steam, whilst the reaction was 0.08 order in artificial gasoline and 0.23 order in steam. Mechanisms have been proposed to account for the dual site surface reaction with dissociative adsorption of isooctane or artificial gasoline and steam. Combined oxidation and steam reforming systems (autothermal reforming) using Pt/CeO2 as a front catalyst bed and Ni-com as the rear bed at the feed conditions of oxygen:carbon (O:C) ratio of ca.1.2 and steam:carbon (S:C) ratio of ca.2, produces ca. 3.5 moles of hydrogen per mole of gasoline fed. The system reaction temperature could be controlled by adjusting the O:C and S:C ratios in feed.

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22

Franzén, Mikael. "Gasoline demand : a comparison of models /". Göteborg : Nationalekonomiska institutionen, Handelshögsk, 1994. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=006320756&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.

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23

Price, Philip Daniel. "Direct injection gasoline engine particulate emissions". Thesis, University of Oxford, 2009. http://ora.ox.ac.uk/objects/uuid:35c0d6bf-bde3-4ef0-a87e-4af89a94b16f.

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Direct fuel injection technology is increasingly being applied to the spark ignition internal combustion engine as one of the many actions required to reduce the CO2 emissions from road transport. Whilst the potential for CO2 reductions is compelling, the technology is not without disadvantages. Early examples typically emitted over an order of magnitude more Particulate Matter (PM) than vehicles with conventional spark ignition engines. Consequently, future revisions to European and North American exhaust emissions legislation are likely to regulate the particulate emissions from vehicles with direct injection gasoline engines. This thesis undertakes to investigate a) instrumentation capable of simultaneously resolving the number concentration and size distribution of particles in the 5-1000 nm size range and b) the factors affecting the PM emissions from spark ignition engines with direct fuel injection. The first objective is achieved by evaluation and comparison of a differential mobility spectrometer; photo-acoustic soot sensor; condensation particle counter and electrical low pressure impactor. To address the second question, a differential mobility spectrometer is applied to quantify the PM emissions from a number of direct injection gasoline engines, together with investigation of their dependence on various calibratable parameters, operating temperature and fuel composition. The differential mobility spectrometer showed good agreement with the other more established instruments tested. Moreover, it exhibited a faster time response and finer resolution in particle size. The number weighted size distribution of the PM emitted was typically lognormal with either one or two modes located between 20 and 100 nm. Chemical analysis of PM samples showed the presence of elemental carbon, volatile organic material and sulphates. Transient PM measurements enabled short time-scale events such as mode switching between homogeneous and stratified mixture preparation to be identified. PM number concentrations in stratified mode exceeded those in homogeneous mode by a factor of 10-100. Dynamometer based experiments showed that PM emissions increase for rich air fuel ratios, retarded fuel injection and advanced ignition events. They also demonstrated a strong dependence on fuel composition: the highest PM emissions were measured with an aromatic fuel, whereas blending alcohols such as methanol or ethanol tended to suppress PM emissions, particularly in the accumulation mode size range. These measurements are amongst the first of their kind and demonstrate the applicability of the differential mobility spectrometer to the measurement of ultra-fine particulate emissions from engines with direct fuel injection systems. Numerous explanations are put forward to describe the data obtained, together with suggestions for future work on PM control and abatement.

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24

Anderson, Cody Allen. "Permeation Sampling of BTEX and Gasoline". University of Akron / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=akron1279115371.

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Brewer, Jed. "Competition in the Retail Gasoline Industry". Diss., The University of Arizona, 2007. http://hdl.handle.net/10150/195202.

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This dissertation examines competition in the retail gasoline industry. The first chapter highlights the importance of gasoline in modern society, introduces my work, and places it in the context of the existing academic literature.The second chapter details the institutional structure and profitability of the industry. The vast majority of retail gasoline stations are not directly owned and operated by major oil companies. Instead, most stations are set up under other contractual relationships: lessee-dealer, open-dealer, jobber-owned-and-operated, and independent. Gasoline retailers make relatively low profits, as is the case in many other retail industries, and are substantially less profitable than major oil companies. Gas stations also make less money when retail prices are climbing than when they are falling. As prices rise, total station profits are near zero or negative. When retail prices are constant or falling, retailers can make positive profits.The third chapter describes the entry of big-box stores into the retail gasoline industry over the last decade. The growth of such large retailers, in all markets, has led to a great deal of controversy as smaller competitors with long-term ties to the local community have become less common. I estimate the price impact that big-box stores have on traditional gasoline retailers using cross-sectional data in two geographically diverse cities. I also examine changes in pricing following the entry of The Home Depot into a local retail gasoline market. The results show that big-box stores place statistically and economically significant downward pressure on the prices of nearby gas stations, offering a measure of the impact of the entry of a big-box store.Chapter 4 examines the nature of price competition in markets where some competing retailers sell the same brand. The price effect of having more retailers selling the same brand is theoretically unclear. High brand diversity could give individual retailers market power, thereby leading to higher prices. Low brand diversity, though, could act to facilitate collusive behavior, leading to higher prices. I find that prices are higher in markets with high brand diversity.The final chapter of the dissertation summarizes the general findings.

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26

Chasos, Charalambos Antoniou. "CFD simulation of direct injection gasoline sprays". Thesis, Imperial College London, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.440540.

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27

Mitroglou, Nicholas. "Multihole injectors for direct-injection gasoline engines". Thesis, City University London, 2006. http://openaccess.city.ac.uk/8487/.

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High-pressure multi-hole nozzles, carrying a Diesel-derived technology, are believed to be promising Fuel Injection Equipment (FIE) for Direct-Injection (DI) Spark Ignition (SI) gasoline engines. Having explored thoroughly swirl pressure atomisers and their spray behaviour, multi-hole nozzles represent the second-generation injectors. Thus, complete investigation of multi-hole nozzle flow, spray characteristics and their engine performance is a vital part of development of future DI gasoline engines. The internal nozzle flow of an enlarged transparent multi-hole injector was investigated for different flow rates and needle lifts under steady state flow conditions. High-resolution CCD camera and high speed digital video systems were employed to visualize the nozzle flow patterns and cavitation development. The images identified the onset of cavitation in multi-hole gasoline nozzles and revealed the transition from pre-film to film stage cavitation. Cavitation strings were also visualized inside the injection hole that could extend to the needle face. However, these structures are highly unstable and directly affected by needle lift and cavitation number, although it appeared to be independent of the Re, in a behaviour similar to that of multi-hole diesel injectors. The sprays from various high-pressure multi-hole nozzle designs injected into a high-pressure/temperature constant-volume chamber have been visualised and quantified in terms of droplet velocity and diameter with a two-component phase-Doppler Anemometry (PDA) system at injection pressures up to 200bar and chamber pressures varying from atmospheric to 12bar. The overall spray angles relative to the axis of the injector were found to be almost independent of injection and chamber pressure, a significant advantage relative to swirl pressure atomisers. Within the measured range, the effect of injection pressure on droplet size was rather small while the increase in chamber pressure from atmospheric to 12bar resulted in much smaller droplet velocities, by up to fourfold, and larger droplet sizes by up to 40%. The effect of chamber temperature on multi-hole sprays confirmed the expected trends that dictate smaller droplet size distributions as temperature rise from 50 to 90 and 120°C. Additionally, multiple-injection proved to have similar dependencies to the single injection with certain operating limits. Laser-induced fluorescence has been mainly used to characterise the two-dimensional fuel vapour concentration inside the cylinder of a multi-valve twin-spark ignition engine equipped with high-pressure multi-hole injectors. The effects of injection timing, in-cylinder charge motion and injector tip layout have been quantified. The flexibility in nozzle design of the multi-hole injectors has proven to be a powerful tool in terms of matching overall spray cone angle and number of holes to specific engine configurations. Injection timing was found to control spray impingement on the piston and cylinder wall, thus contributing to quick and efficient fuel evaporation. Multipleinjection performed well under certain operating conditions and proved to be a powerful tool in the hands of engine manufacturers. It was confirmed that in-cylinder charge motion plays a major role in engine's stable operation by assisting in the transportation of the air-fuel mixture towards the ignition locations (i.e. spark-plugs) in the way of a uniformly distributed charge or by preserving stratification of the charge depending on operating mode of the engine.

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28

Jiang, Shixun. "Optimization of diesel and gasoline blending operations". Thesis, University of Manchester, 2016. https://www.research.manchester.ac.uk/portal/en/theses/optimization-of-diesel-and-gasoline-blending-operations(1d3d232d-442c-4c94-9e06-afbf10a3203a).html.

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Diesel, one of the main petroleum products, is widely used in industry and transportation. Only high quality diesel product can survive in the more and more competitive market. The optimization methodology for diesel production and management is critical to refineries' profitability. LP/MIP models have been applied in diesel blending planning and scheduling in the last decades. With the benefits of reducing the model scale and computing efforts, LP/MIP models lead to operation results with inaccurate property estimation and profit loss due to the accuracy loss in the linearisation of blending models. To improve model accuracy, more accurate property prediction models for diesel blending should be incorporated into the refinery planning and schedule methods to improve decision making procedure in the case of scheduling for diesel blending, where academic effort is almost absent. A model for planning of refinery diesel streams is developed to optimise the diesel production of a refinery. Nonlinear blending models are applied to calculate blending properties more precisely than conventional linear models. Due to the large number of equations and variables, it may be generated to an infeasible solution if the given initial points are not good enough. To avoid this situation, a solution algorithm is proposed. Based on the NLP planning model, a model for scheduling diesel blending is developed. In order to improve the model accuracy, nonlinear blending correlations are used, which lead to a complicated MINLP problem that cannot be solved by existing MINLP solver directly. A robust solution algorithm is proposed in this thesis to help optimizing the MINLP problem. A case study of diesel production blending scheduling is introduced to illustrate how to model a diesel blending scheduling problem and the efficient and reliability of the solution algorithm. Besides, the proposed MINLP model and the solution algorithm can be extensively applied to other processes in a refinery, such as gasoline blending. Once gasoline blending models are taken into account, the model can be modified to optimize the gasoline blending scheduling problem.

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29

Elias, Brian. "Hazard Assessment of Portable Gasoline Container Flammability". Digital WPI, 2011. https://digitalcommons.wpi.edu/etd-theses/1054.

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"This study considers the flammability hazard associated with the pouring of gasoline from a portable gasoline container (PGC) in an area containing a potential ignition source. In this scenario a flame may propagate into the PGC and cause an explosion if a flammable environment exists along the length of the pour spout and into the PGC headspace. In order to quantify this hazard, experiments are conducted to measure the flammable vapor concentration within this area under various conditions of temperature, liquid volume, and container pour angle. It is found that liquid fuel volumes as high as 30 mL in a 5-gallon PGC are capable of producing a flammable vapors within the PGC headspace. Finally, a mathematical model is presented to predict the flammability hazard under various conditions."

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30

Noel, Michael David 1971. "Edgeworth price cycles in retail gasoline markets". Thesis, Massachusetts Institute of Technology, 2002. http://hdl.handle.net/1721.1/8416.

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Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Economics, 2002.
Includes bibliographical references (p. 135-137).
In this dissertation, I present three essays that are motivated by the interesting and dynamic price-setting behavior of firms in Canadian retail gasoline markets. In the first essay, I examine behavior at the market level for 19 Canadian cities over 574 weeks. I find three distinct pricing patterns: 1. standard cost-based pricing, 2. sticky pricing, and 3. steep, asymmetric retail price cycles that mirror the Edgeworth Cycles of Maskin & Tirole [1988b]. I use a Markov switching regression to estimate the prevalence of the regimes, the pattern of markup in each, and the structural characteristics of the price cycles themselves. Retail price cycles prevail in over 40% of the sample. I show they are more prevalent when there is a greater penetration of small, independent firms. The cycle is accelerated and amplified in markets with very many small firms. Where small firms are few, sticky pricing dominates. In the second essay, I present a new station-level micro-dataset that reveals especially strong retail price cycles in the Toronto market. I show that it is large firms who first reset each new cycle by significantly raising prices. The one-time average price increase is 5.6 cents per liter, or 170% of the average margin. The magnitude of the increase is decreasing in the previous markup and increasing in expected future wholesale prices. I show that small independent firms wait longest before responding, and the entire process is usually complete in 24 hours. From the top of the cycle, I find small firms undercut first and trigger each new round of tit-for-tat price undercutting.
(cont.) In the third essay, I explore the theoretical conditions that best foster price cycles and how those conditions affect the character of the cycles themselves. Using computational techniques, I search for Markov Perfect Equilibria under several models of duopoly and triopoly and for various model-specific parameter values. I consider degrees of differentiation, capacity constraints, sharing rules, discount factors and initial beliefs about price leading behavior. I find Edgeworth price cycles with interesting characteristics under many conditions and focal prices under others.
by Michael David Noel.
Ph.D.

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31

Leach, Felix Charles Penrice. "Particulate emissions from gasoline direct injection engines". Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:ea9c349e-5ade-4878-b758-c9a050c8f069.

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Direct injection spark ignition (DISI) engines are the next generation of gasoline fuelled engines. Their greater fuel economy and reduced CO2 emissions compared with port fuel injection (PFI) engines has led to their popularity. However, DISI engines produce a greater number of particulate matter (PM) emissions than PFI engines. Concern over the health effects of PM emissions, and forthcoming European legislation to regulate them from gasoline powered vehicles has led to an increased interest in the study of PM formation, measurement, and characterisation. A model was developed by Aikawa et al, the PM index, correlating PM emissions with fuel composition. PM emissions are thought to be linked both to the vapour pressure (VP) and the double bond equivalent (DBE) of the components of the fuel. However, there was no independent control of these parameters and the study was undertaken on a PFI engine. In this thesis, experiments have been conducted to validate this model and extend it, as the PN index, to DISI engines. Fuels have been designed using Raoult’s law and UNIFAC (with careful consideration of octane number) such that the DBE and VP of the fuel mix could be varied independently. The design of the fuels was such that the component parts would co-evaporate upon injection into the cylinder, ensuring a homogeneous mixture of the components at the point of ignition. The PN index has been tested on a single cylinder engine, at a matrix of test points, using these model fuels, and their PM emissions have been analysed using a Cambustion DMS500. The results show that the PN index is followed closely using model fuels, provided that these model fuels contain a ‘light-end’ (in this case 5 % v/v n-pentane). Imaging of in-cylinder evaporation and in-cylinder measurement of hydrocarbons shows how the composition of model fuels affects their PM emissions. The PN index has also been tested using commercial fuels on a single cylinder engine and a Jaguar V8 engine; the results again show that the PN index is also an excellent predictor of PN emissions for market fuels from both of these engines. PN emissions have been evaluated from two fuels representing the EU5 reference fuel specification, developed using the PN index to give a difference in PM emissions. Testing these fuels on both a single cylinder engine and a Jaguar V8 engine has shown up to a factor of three variation in observed PN emissions. This has important implications for forthcoming European emissions legislation. The results of these tests were fed into the recommendations for the EU6 reference fuel specification. The PN index has also been investigated in a Jaguar V6 engine with five different fuels with a spread of calculated PN indices over a simulated NEDC. Here the PN emissions have been measured using two PN, and one PM instrument and the results compared. The results show that the trends of the PN index are followed, but not as closely as predicted. Detailed analysis shows that this discrepancy is due to other effects, for example cold start, dominating the PN emissions in certain phases. PN emissions have been measured from a highly boosted engine at a variety of operating points using 14 different fuels. It has been shown that for a large variety of engine operating parameters PN emissions from highly boosted engines behave as expected. When changing the fuels, the results show that a variation of over three orders of magnitude can be observed. The predictions of the PN index are inconclusive however, with further work suggested to fully evaluate the PN index on highly boosted engines.

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32

Buarque, Hugo Leonardo de Brito. "Prediction of gasoline properties from composition data". Universidade Federal do CearÃ, 2006. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=172.

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AgÃncia Nacional do PetrÃleo
Commercial gasolines are normally produced by blending hydrocarbon fractions obtained from the distillation of crude oil or from other petrochemical or refining processes, and carried through in order to comply with a variety of legal and ambient specifications at minimum cost. The quality for the use and commercialization of gasolines is evaluated through certain characteristics specified by governmental regulation. Such characteristics are usually determined by different methodologies and experimental techniques, since those depend on their constituents and their respective concentrations with a high complexity. Thus, blending of gasolines in petrochemical and refining industries is sometimes a very laborious procedure. The prediction of fuel properties from composition data is growing in importance in the last few years. Methods of group contribution have been used in the last decades to predict properties of pure organic compounds and some mixture parameters (e.g., UNIFAC). However, most of the recent studies use artificial neural networks as a technique for prediction for fuel properties using the composition of classes of constituents or key-compounds as input data. The main advantage of a neural network is its capacity to extract general and unknown information for certain series of data (training), supplying useful and fast models for prediction. However, the use of neural networks trained to predict properties of fuels produced from one given combination of petroleum fractions can not be suitable in the prediction of the characteristics of other gasolines produced from other origins due to the complexity and variability of gasoline composition. In this study, methods of multiple linear regression and artificial neural networks have been evaluated in the correlation and prediction of gasoline properties from information of composition obtained by gas chromatography, as well as a methodology for prediction of properties using a hybrid method composed of neural networks and group contribution. The developed model is evaluated and compared to other methods, revealing to be sufficiently promising for prediction of properties of pure components and complex mixtures.
As gasolinas comerciais sÃo normalmente produzidas a partir de combinaÃÃes de fraÃÃes oriundas da destilaÃÃo do petrÃleo ou de outros processos petroquÃmicos e de refino e realizadas de modo a atender uma variedade de especificaÃÃes legais e ambientais, com o mÃnimo de custo possÃvel. A qualidade para o uso e comercializaÃÃo de uma gasolina Ã avaliada atravÃs de certas caracterÃsticas especificadas por leis e normas governamentais. Estas caracterÃsticas sÃo normalmente determinadas por diferentes metodologias e tÃcnicas experimentais, haja vista que dependem dos seus constituintes e suas respectivas concentraÃÃes com uma complexidade bastante elevada, tornando a formulaÃÃo da gasolina originada em refinarias e petroquÃmicas, um procedimento muitas vezes bastante laborioso. O intuito de se predizer propriedades de derivados de petrÃleo a partir de dados de composiÃÃo Ã antigo e vem crescendo em importÃncia nos Ãltimos anos. MÃtodos de contribuiÃÃo de grupos tÃm sido utilizados ao longo das Ãltimas dÃcadas para predizer propriedades de compostos orgÃnicos puros e alguns parÃmetros de misturas (e.g., UNIFAC). Entretanto, a maior parte dos estudos mais recentes utiliza redes neurais artificiais como tÃcnica para prediÃÃo de propriedades de combustÃveis usando a composiÃÃo de grupos de compostos ou mesmo de compostos-chave como informaÃÃo de entrada. A principal vantagem de uma rede neural Ã sua capacidade de extrair informaÃÃes gerais e desconhecidas para certa sÃrie de dados (treinamento), fornecendo modelos de prediÃÃo Ãteis e rÃpidos tanto para sistemas lineares como nÃo-lineares. PorÃm, dada a complexidade e variabilidade dos constituintes das gasolinas, a utilizaÃÃo de redes neurais treinadas para modelar as propriedades destes combustÃveis produzidos a partir de uma dada combinaÃÃo de fraÃÃes petrolÃferas pode nÃo se adequar na prediÃÃo das caracterÃsticas de gasolinas obtidas a partir de uma outra origem. Neste estudo, mÃtodos de regressÃo linear mÃltipla e redes neurais artificiais foram avaliados na correlaÃÃo e prediÃÃo de propriedades de gasolinas a partir de informaÃÃes de composiÃÃo obtidas por cromatografia gasosa, como tambÃm foi desenvolvida uma metodologia de prediÃÃo de propriedades utilizando um mÃtodo hÃbrido de redes neurais e contribuiÃÃo de grupos. O modelo desenvolvido Ã avaliado e comparado aos demais, mostrando-se bastante promissor para prediÃÃo de propriedades de componentes puros e misturas mais complexas.

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33

Yeh, Kuei-Jyum. "Degradation of gasoline oxygenates in the subsurface". Diss., This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-06062008-172029/.

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Maugham, Robin. "Dilution torque control of a gasoline engine". Thesis, University of Bath, 2002. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.268735.

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Buttarello, Karina Zoboli. "Análise da impedância acústica na gasolina". Universidade de São Paulo, 2003. http://www.teses.usp.br/teses/disponiveis/18/18135/tde-16022016-120602/.

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Este trabalho analisa a qualidade dos combustíveis derivados de petróleo através de suas propriedades acústicas, visando assim um monitoramento contínuo e instantâneo. Analisa a variação da impedância acústica da gasolina com acréscimo de vários componentes como: tolueno, óleo diesel, querosene e álcool anidro. Os resultados obtidos mostram uma variação significativa embora não linear da impedância acústica nos combustíveis derivados de petróleo com acréscimo de tais substâncias.
This work is related with research project focused on the development of low cost and robust quality monitoring equipment and methods, suitable for application in the production of petrochemical compounds. The main objective of this work is to assess the quality of automotive gasoline through the analysis of its acoustic properties. More specifically, pure gasoline\'s acoustic impedance (defined as the product between its density and the velocity of propagation of an acoustic wave) is analyzed with respect to the addition of toluene, kerosene, ethanol and diesel fuel. Results show that the acoustic impedance is sensitive to the addition of such components, although this relation may be non-linear in some cases.

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36

Dennison, James E. "Physiologically-based pharmacokinetic modeling of simple and complex mixtures of gasoline and the gasoline components n-hexane, benzene, toluene, ethylbenzene, and xylene". Access citation, abstract and download form; downloadable file 10.35 Mb, 2004. http://wwwlib.umi.com/dissertations/fullcit/3131667.

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37

Böhme, Thomas Rainer. "Dynamic modeling of auto-thermal gasoline fuel processors /". Zürich : Measurement and Control Laboratory, ETH Zürich MLK, 2006. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=17703.

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38

Gidda, Tejwant Singh. "Passive volatilization behaviour of gasoline in unsaturated soils". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/mq24467.pdf.

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39

Mullett, Jack Daniel. "Laser-Induced Ignition Systems for Gasoline Automotive Engines". Thesis, University of Liverpool, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.507466.

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40

Pease, Nick. "Top ring zone oil sampling in gasoline engines". Thesis, De Montfort University, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.391904.

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41

Jamroz, Przemek R. 1977. "Injector deposit formation in gasoline direct injection engines". Thesis, Massachusetts Institute of Technology, 2002. http://hdl.handle.net/1721.1/89343.

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42

Niekamp, Troy S. (Troy Steven). "Translation of dilution tolerance for gasoline SI engine". Thesis, Massachusetts Institute of Technology, 2013. http://hdl.handle.net/1721.1/81616.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2013.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 69-70).
There are a variety of fuel improvement strategies being developed for spark ignition engines which use dilution. Many of these technologies use a combination of different diluents. It is impractical in optimizing these technologies to test every possible combination of diluents. The purpose of this study was to determine a relationship between the various diluents and combustion related output parameters. One of these key outputs was determining the dilution tolerance for an engine. In order to achieve this goal, the fundamental of combustion were studied. The results from this study will be useful in developing more aggressive engine control strategies. Dilution has been studied extensively in previous research. Its effects are well known. Primarily, it reduces peak combustion temperatures. This can be used as an effective means to reduce losses and hazardous emissions. Too much dilution, however, and the combustion stability is compromised. To facilitate this project, an engine was fully instrumented. Experiments were performed for a variety of operating conditions and diluents. Results were then used to correlate the diluent properties and quantities to combustion outputs. Adiabatic flame temperature was first attempted as the key metric for correlation. This metric proved to be unsuitable for developing correlations. Later, a new metric was computed by taking a linear combination of diluents. This was found to offer superior results. Using this metric along with other basic engine measurements, correlations were developed between the diluents and engine output parameters. These output parameters include dilution tolerance, exhaust temperature, NOx emissions, and combustion bum durations.
by Troy S. Niekamp.
S.M.

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43

GuimarÃes, Ãngela. "The Etanol and the Gasoline are Perfect Substitutes?" Universidade Federal do CearÃ, 2008. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=2421.

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The relative domestic prices behavior for fuels (relationship among price of ethanol and gasoline) was analyzed accord to panel monthly ones on 27 Brazilian units during the period from July 2001to February 2008. They released by ANP and through Box-Jenkins methodology. It was empirically verified that relative prices seem to follow a first-order autoregressive process, AR(1), with an average ratio equal marginal utility of ethanol (sugarcane) and gasoline (fossil fuel) liters, which is equal technical coefficient of 70 %. This result suggests that owners of dual-fuel ehicle technology in the face of consumer arbitrage became the natural official regulator of this market such as short as long term.
O comportamento dos preÃos relativos nacionais dos combustÃveis lÃquidos (relaÃÃo entre o preÃo do Ãlcool e o da gasolina) foi analisado com base no painel desses preÃos mensais, em 27 unidades brasileiras, durante o perÃodo de julho de 2001 a fevereiro de 2008, disponibilizados pela ANP e por meio da Metodologia Box-Jenkins. Constatou-se empiricamente que os preÃos relativos parecem seguir um processo auto-regressivo da classe AR(1), com mÃdia igual Ã razÃo entre as utilidades marginais do litro do Ãlcool e do litro da gasolina, ou seja, igual ao coeficiente tÃcnico de 70%. Esse resultado sugere que os proprietÃrios de carros bicombustÃveis, mediante o poder de arbitragem, se tornaram o agente regulador natural deste mercado, tanto no curto quanto no longo prazo.

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44

Abdelkarim, Nazar B. H. "Numerical modelling of direct-injection gasoline fuel sprays". Thesis, Loughborough University, 2005. https://dspace.lboro.ac.uk/2134/34055.

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This thesis presents a numerical study of the break-up and atomisation of gasoline fuel sprays injected into atmospheric flow conditions and environments related to combustion chamber conditions. Calculations of the fuel break-up process were achieved by four different models: Taylor Analogy Break-up (TAB), the wave instability theory (WAVE), the Hybrid Sheet-TAB and the Hybrid WAVE-FIPA models. The TAB model relates the break-up process to the droplet oscillations; whereas the WAVE models calculate the fuel break-up from the unstable waves on the droplet surface. The modified version of the TAB model, called the Hybrid Sheet-TAB model delays the start of the break-up further downstream from the nozzle tip. A new hybrid model, the WAVE-FIPA model, divides the spray atomisation processes into a primary stage, where the WAVE model is used, and a secondary stage, which is simulated using experimental correlations to calculate the break-up time for the low Weber number droplets.

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45

Smelser, Jennifer Beasley. "Oxygen depletion shutdown algorithm for portable gasoline generators". Thesis, [Tuscaloosa, Ala. : University of Alabama Libraries], 2009. http://purl.lib.ua.edu/2178.

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46

Osborne, Richard J. "Controlled auto-ignition processes in the gasoline engine". Thesis, University of Brighton, 2010. https://research.brighton.ac.uk/en/studentTheses/1bf3c062-1d30-4d94-8c68-3c00da31e22d.

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Controlled auto-ignition (CAI) combustion – also described as homogeneous charge compression ignition (HCCI) combustion – was investigated. The primary experiments concerned a direct-injection single-cylinder gasoline engine equipped with a poppet valve combustion system. This engine was operated with both the two-stroke working cycle and the four-stroke cycle. The engine experiments were used to establish combustion characteristics and the envelope of operation for CAI combustion, and to investigate the influence of a number of engine parameters including engine speed and load, air-fuel ratio, intake-air heating and exhaust-port throttling. Results from one-dimensional fluid-dynamic calculations were used to support the main data set and to develop hypotheses concerning CAI combustion in practical gasoline engines. Images from parallel investigations using an equivalent optical-access engine, and three-dimensional fluid-dynamic calculations, were used to supplement the results generated by the author and to further develop and test understanding of gasoline CAI processes. Finally practical implementation of CAI combustion in passenger vehicles was considered, including possible routes to series production of CAI engines.

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47

Beavis, Nicholas J. "Numerical studies of gasoline direct injection engine processes". Thesis, Loughborough University, 2017. https://dspace.lboro.ac.uk/2134/25230.

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The GDI engine has a number of practical advantages over the more traditional port-fuel injection strategy, however a number of challenges remain the subject of continued research in an attempt to fully exploit the advantages of the GDI engine. These include complex in-cylinder flow fields and fuel-air mixing strategies, and significant temporal variation, both through an engine cycle and on a cycle-by-cycle basis. Despite advances in experimental techniques, the relative difficulty and cost of taking detailed measurements remains high, thus computational techniques are an integral part of research activities. The research work presented in this thesis has focused on the use of detailed 3D-CFD techniques for investigating physical phenomena of the in-cylinder flow field and fuel injection process in a single cylinder GDI engine with early injection event. A detailed validation of the numerical predictions of the in-cylinder flow field using both the RANS RNG k-ε turbulence model and the Smagorinsky LES SGS turbulence model was completed with both models showing good agreement against available experimental results. A detailed validation of the numerical predictions of the fuel injection process using a Lagrangian DDM and both RANS RNG k-ε turbulence model and Smagorinsky LES SGS turbulence model was completed with both models showing excellent agreement against experimental data. The model was then used to investigate the in-cylinder flow field and fuel injection process including research into: the three dimensional nature of the flow field; intake valve jet flapping, characterisation, causality and CCV, and whether it could account for CCV of the mixture field at spark timing; the anisotropic characteristics of the flow field using both the fluctuating velocity and turbulence intensity, including the increase in anisotropy due to the fuel injection event; the use of POD for quantitatively analysing the in-cylinder flow field; investigations into the intake valve, cylinder liner and piston crown spray plume impingement processes, including the use of a multi-component fuel surrogate and CCV of the formed liquid film; characterisation and CCV of the mixture field though the intake and compression strokes up to spark timing. Finally, the predicted turbulence characteristics were used to evaluate the resultant premixed turbulent combustion event using combustion regime diagrams.

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48

Akma, Tengku N. "Miller cycle combustion strategy for downsized gasoline engines". Thesis, Loughborough University, 2017. https://dspace.lboro.ac.uk/2134/32421.

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In response to the global concerns towards oil scarcity and climate change, the automotive industry is currently focusing on improving fuel economy and reducing exhaust emissions. Modern downsized gasoline engines that come with a package that includes a boosting system, variable valve train and direct fuel injection system is effective for fuel economy improvement and emission reduction. However, the knocking issue becomes severe at high load operations as a result of the high intake boosting pressure. In regard to the part load conditions, the gas exchange process requires extra work to draw in air into the cylinder due to a lower amount of pressure in the intake manifold caused by the restriction of the throttle plate. The Miller cycle is regarded as a potential strategy of knock control for downsized gasoline engines. Extensive works have sought to examine the performance improvement via the Miller cycle, yet only limited research has been conducted on the manner in which it can influence knock suppression. The focus of this thesis is to investigate early and late intake valve closing timings in terms of how they affect the compression process, the ability to suppress engine knock and meet the power output required at high loads for spark-ignited gasoline engines. Apart from that, this research also demonstrates the Miller cycle potential by utilising fully variable valve timing in controlling the load at the part load condition without using a throttle. The early intake valve closing with different valve lifts was tested in order to investigate the impact during the gas exchange process, particularly the pumping losses and the potential to improve fuel economy. This study includes both experimental and simulation studies. A Lotus single-cylinder research engine referred to as SCORE was mainly used for the experimental component of the study. The simulation work was conducted using a one-dimensional spark ignition engine model built in the Ricardo WAVE software for naturally-aspirated and downsized engines. The engine model values are validated against the experimental values from the Lotus SCORE and Lotus SABRE engines. The combustion model with a reduced kinetics mechanism was validated using a Rover K-series engine. A broad matrix of the engine operations has been investigated combining a variety of engine speeds and engine loads. The Miller cycle effects on knock suppression in a downsized engine environment have been investigated in three parts, namely the Miller cycle at different speed-load, knock suppression with extreme Miller cycle, and knock analysis with combustion kinetics. Through the works, the Miller cycle has demonstrated its capability to suppress engine knocking in a more efficient manner as opposed to the standard engine operation. This is contributed by the fact that early and late intake valve closings could affect the end gas condition at the end of the compression stroke, thus making it possible to suppress the engine knocking. The experimental study for controlling load without using throttle under the naturally-aspirated condition found that the Miller cycle with an early intake calve closing strategy able to improve fuel consumption by reducing pumping losses. The downsized engine condition, which has been evaluated via modelling work, also showed an improved performance trend using the unthrottled Miller cycle strategy. The open cycle and close cycle efficiencies have improved through the Miller cycle implementation. The contribution of this work is made in order to establish the comparison of the Miller cycle strategy in suppressing knocking between the early intake valve closing and late intake valve closing under a boosted environment. For the part load condition of the downsized engine, the research contributes to the existing body of knowledge by comparing the throttle-less Miller cycle and the standard throttled operation as a load control strategy.

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49

Penner, Giovanni Chaves. "Estudos laboratoriais da contaminação do solo por gasolina com o uso de detetor de fotoionização". Universidade de São Paulo, 2000. http://www.teses.usp.br/teses/disponiveis/18/18138/tde-17082001-120419/.

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A presente pesquisa trata de calibrar, a ferir e utiliza em laboratório um detetor de fotoionização (método de campo) proveitoso na caracterização de áreas contaminadas por vazamentos de gasolina; comparar as informações do detetor com os resultados obtidos com balança analítica; comparar os resultados de fluxo de massa medido com o previsto pelo modelo JURY contido no software APIDSS 2.0 O detetor mostrou-se útil como primeira ferramenta na caracterização de áreas contaminadas recentemente (até 100 dias). Para áreas onde a contaminação esteja em uma fase mais avançada o aparelho mostrou-se útil na detecção de alterações; os modelos desenvolvidos com base nos resultados obtido com balança e com o detetor de fotoinização apresentaram resultados satisfatórios para o período de ensaio; as comparações realizadas com o software APIDSS 2.0 serviram para a confirmação dos resultados obtidos.
The present research aims at gauging, checking and using a photoionization detector (field method) in laboratory advantageous to the characterization of areas polluted by leaks of gasoline; to compare the information of the detector with the results obtained in the analytic scale; to compare the results of the measured mass flow with those foreseen by the model JURY of the software APIDSS 2.0. The detector showed to be useful as a first tool in the characterization of areas recently contaminated (up to 100 days). To areas where the contamination is in a more advanced phase, the apparel showed to be useful in the detection of alterations; the development of models based on the results obtained with a scale and with the photoionization detector presented satisfactory results for the rehearsal period; the comparisons accomplished by the software APIDSS 2.0 confirmed the obtained results.

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D´Oliveira, Rúbia Baptista. "Quais são os determinantes do preço do combustível gasolina no mercado brasileiro?" reponame:Repositório Institucional do FGV, 2018. http://hdl.handle.net/10438/20203.

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Submitted by Rubia Oliveira (rubia.doliveira@hotmail.com) on 2018-02-19T22:50:04Z No. of bitstreams: 1 Rúbia Baptista D´Oliveira_ determinantes preço de revenda combustível gasolina - OFICIAL.pdf: 759138 bytes, checksum: 39a8f098ede88082e289c9fed7ff4407 (MD5)
Approved for entry into archive by Thais Oliveira (thais.oliveira@fgv.br) on 2018-02-20T18:58:03Z (GMT) No. of bitstreams: 1 Rúbia Baptista D´Oliveira_ determinantes preço de revenda combustível gasolina - OFICIAL.pdf: 759138 bytes, checksum: 39a8f098ede88082e289c9fed7ff4407 (MD5)
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Esse artigo analisa os determinantes do preço do combustível gasolina. Atualmente a gasolina é utilizada por aproximadamente 60% dos veículos leves no Brasil e tem uma parcela relevante no consumo das famílias, portanto é preciso que o consumidor conheça profundamente como funciona o mercado desse produto, desde o produtor até o consumidor final, e principalmente que saiba como é formado o seu preço. O artigo busca então compreender quais são os determinantes do preço de revenda do combustível gasolina no mercado brasileiro e também entender por que ocorrem divergências nos preços dentro de uma mesma cidade.
This article analyzes the determinants of the price of gasoline fuel. Currently, gasoline is used by approximately 60% of light vehicles in Brazil, and has a significant share of household consumption, so it is necessary for the consumer to know deeply how the market of this product works, from the producer to the final consumer, and especially knows how its price is formed. The article then seeks to understand the determinants of the price of gasoline fuel in the Brazilian market, and also to understand why there are divergences in prices within the same city.

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