Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-07-08T21:06:56Z No. of bitstreams: 1 FabioPimentaDeLira_DISSERT.pdf: 2588802 bytes, checksum: 309b81889459c9056d686910dd512bf9 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-07-12T19:50:05Z (GMT) No. of bitstreams: 1 FabioPimentaDeLira_DISSERT.pdf: 2588802 bytes, checksum: 309b81889459c9056d686910dd512bf9 (MD5) / Made available in DSpace on 2016-07-12T19:50:05Z (GMT). No. of bitstreams: 1 FabioPimentaDeLira_DISSERT.pdf: 2588802 bytes, checksum: 309b81889459c9056d686910dd512bf9 (MD5) Previous issue date: 2015-11-30 / O presente estudo trata de uma an?lise, em car?ter experimental, do consumo de combust?vel de um veiculo flex, operando com diferentes misturas de gasolina e etanol em tr?fego urbano, o que permite obter resultados mais condizentes com a realidade do motorista, haja vista que os ?ndices de consumo aferidos pelo INMETRO n?o levam em considera??o o real cen?rio que a popula??o enfrenta diariamente em seus deslocamentos urbanos, possibilitando assim a escolha mais economicamente vi?vel da mistura gasolina/etanol, acarretando numa redu??o dos custos e, possivelmente, uma diminui??o nos ?ndices de emiss?o de poluentes. Atualmente, os fabricantes de ve?culos flex recomendam o abastecimento com etanol, caso o valor deste n?o ultrapasse 70% do valor da gasolina comum, entretanto, os ve?culos com a tecnologia flex, possibilitam operar com qualquer percentual de mistura no tanque de combust?vel, por?m, hoje, muitos dos propriet?rios desses ve?culos n?o utilizam esse recurso com efici?ncia, por desconhecerem essa possibilidade de mistura ou pela raz?o de n?o existir um estudo mais profundo em rela??o ao percentual ideal da mistura que proporcione um maior rendimento com um custo inferior ao proposto pelos fabricantes. / This study is an analysis, on a trial basis, the fuel consumption of a Flex vehicle, operating with different mixtures of gasoline and ethanol in urban traffic, allowing more consistent results with the reality of the driver. Considering that most owners unaware of the possibility of mixing the fuel at the time of supply, thus enabling the choice of the most economically viable mixing gasoline / ethanol, resulting in lower costs and possibly a decrease in pollutant emission rates. Currently, there is a myth created by the people that supply ethanol only becomes viable if the value of not more than 70% of regular gasoline. However vehicles with this technology make it possible to operate with any percentage of mixture in the fuel tank, but today many of the owners of these vehicles do not use this feature effectively, because they ignore the possibility of mixing or the reason there is a deeper study regarding the optimal percentage of the mixture to provide a higher yield with a lower cost than proposed by the manufacturers.

Made available in DSpace on 2014-12-17T14:52:41Z (GMT). No. of bitstreams: 1 ThaziaVSS.pdf: 623176 bytes, checksum: f3522bf5126d51241ee4b1cc03a0a3ad (MD5) Previous issue date: 2008-11-17 / This thesis intends to show the level of pollutant emissions in the State of Rio Grande do Norte, generated by the final consumption of energy in the many different sectors of the economy. This information was obtained from the energetic matrix and from the pollutant emissions of the State and the data was taken from the Balan?o Energ?tico Estadual and from the Sistema de Informa??es Energ?ticas da Olade. The result will permit to identify the energy and most polluting economic sectors in Rio Grande do Norte, contributing to energy planning, giving direction to the public policy development that aim at the change of the energy matrix of the State. Also with the objective of reducing pollutant emissions through rationalization, efficiency and energy substitution, which the main objective is to promote the economic development based on energy consumption of less harmful impact on the environment, contributing to establishment of sustainable development / A disserta??o pretende apresentar o n?vel de emiss?es em que se encontra o Estado do Rio Grande do Norte, geradas com o consumo final de energ?ticos nos diversos setores da economia. Esta informa??o foi obtida a partir da matriz energ?tica e de emiss?es poluentes do Estado, cujos dados foram extra?dos do Balan?o Energ?tico Estadual e do Sistema de Informa??es Energ?ticas da Olade. O resultado poder? identificar os energ?ticos e os setores econ?micos mais poluidores do RN, podendo auxiliar o planejamento energ?tico, direcionando o desenvolvimento de pol?ticas p?blicas que visam altera??o gradativamente da matriz energ?tica do RN com vistas ? redu??o de emiss?es poluentes atrav?s da racionaliza??o, efici?ncia e substitui??o energ?tica, cujo objetivo ? promover o desenvolvimento econ?mico, pautado no consumo de energia, de forma menos danosa ao meio ambiente, contribuindo tamb?m para o alcance de um desenvolvimento sustent?vel

Made available in DSpace on 2014-12-17T15:01:52Z (GMT). No. of bitstreams: 1 ManoelRF_TESE_PARCIAL.pdf: 3699462 bytes, checksum: 4db868ae1dcdf8497e51d1aa5771684c (MD5) Previous issue date: 2011-05-16 / The industry, over the years, has been working to improve the efficiency of diesel engines. More recently, it was observed the need to reduce pollutant emissions to conform to the stringent environmental regulations. This has attached a great interest to develop researches in order to replace the petroleum-based fuels by several types of less polluting fuels, such as blends of diesel oil with vegetable oil esters and diesel fuel with vegetable oils and alcohol, emulsions, and also microemulsions. The main objective of this work was the development of microemulsion systems using nonionic surfactants that belong to the Nonylphenols ethoxylated group and Lauric ethoxylated alcohol group, ethanol/diesel blends, and diesel/biodiesel blends for use in diesel engines. First, in order to select the microemulsion systems, ternary phase diagrams of the used blends were obtained. The systems were composed by: nonionic surfactants, water as polar phase, and diesel fuel or diesel/biodiesel blends as apolar phase. The microemulsion systems and blends, which represent the studied fuels, were characterized by density, viscosity, cetane number and flash point. It was also evaluated the effect of temperature in the stability of microemulsion systems, the performance of the engine, and the emissions of carbon monoxide, nitrogen oxides, unburned hydrocarbons, and smoke for all studied blends. Tests of specific fuel consumption as a function of engine power were accomplished in a cycle diesel engine on a dynamometer bench and the emissions were evaluated using a GreenLine 8000 analyzer. The obtained results showed a slight increase in fuel consumption when microemulsion systems and diesel/biodiesel blends were burned, but it was observed a reduction in the emission of nitrogen oxides, unburned hydrocarbons, smoke index and f sulfur oxides / A ind?stria, ao longo dos anos, vem trabalhando no sentido de melhorar a efici?ncia dos motores. Mais recentemente surgiu, tamb?m, a necessidade de reduzir as emiss?es de poluentes para se adequar ?s severas leis ambientais. Isto tem despertado o interesse de desenvolver pesquisas no sentido de substituir os combust?veis derivados do petr?leo por diversos tipos de combust?veis menos poluentes, tais como: misturas de ?leo diesel com ?steres de ?leos vegetais e ?leo diesel com ?leos vegetais e ?lcool, emuls?es e microemuls?es. Este trabalho tem como objetivo desenvolver sistemas microemulsionados a partir de tensoativos n?o i?nicos dos grupos nonilfenois etoxilados e ?lcoois l?uricos etoxilados, misturas com etanol/diesel e misturas diesel/biodiesel para uso em motores diesel. Em uma primeira fase, visando selecionar os sistemas microemulsionados, foram obtidos diagramas tern?rios das misturas, sendo os sistemas compostos por: tensoativos n?o-i?nicos, ?gua como fase polar e como fase apolar o diesel e/ou misturas diesel/biodiesel. Os sistemas microemulsionados e as misturas, que representam os combust?veis estudados, foram caracterizados quanto ? massa espec?fica, a viscosidade, o ?ndice de cetano e o ponto de fulgor. Tamb?m foram avaliados o efeito da temperatura nos sistemas microemulsionados, o desempenho do motor, e as emiss?es de mon?xido de carbono, ?xidos de nitrog?nio, hidrocarbonetos n?o queimados e fuma?a de todos os sistemas. Os ensaios de consumo espec?fico e das emiss?es em fun??o da pot?ncia foram realizados em um motor de ciclo diesel em uma bancada dinamom?trica e o analisador de emiss?es GreenLine 8000. Os resultados mostraram um pequeno aumento no consumo espec?fico para os combust?veis microemulsionados, nas misturas diesel/biodiesel em rela??o ao diesel puro, por?m com uma redu??o nas emiss?es de ?xidos de nitrog?nio, hidrocarbonetos n?o queimados, ?ndice de fuma?a e ?xidos de enxofre