• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 2
  • Tagged with
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

An?lise preditiva a partir da caracteriza??o das emiss?es gasosas e do ?leo lubrificante em frotas com motoriza??o a diesel

Sousa, Eduardo Henrique Viana de 30 August 2010 (has links)
Made available in DSpace on 2014-12-17T14:58:03Z (GMT). No. of bitstreams: 1 EduardoHVS_DISSERT.pdf: 4888448 bytes, checksum: 16ede4f993cb59d4e084c847af90483e (MD5) Previous issue date: 2010-08-30 / This work was motivated by the importance of conducting a study of vehicle emissions in captive fleets with diesel engine, coupled with the predictive maintenance plan. This type of maintenance includes techniques designed to meet the growing market demand to reduce maintenance costs by increasing the reliability of diagnoses, which has increased interest in automated predictive maintenance on diesel engines, preventing problems that might evolve into routine turn into serious situations, solved only with complex and costly repairs, the Reliability Centered Maintenance, will be the methodology that will make our goal is reached, beyond maintaining the vehicles regulated as fuel consumption and emissions. To Therefore, technical improvements were estimated capable of penetrating the automotive market and give the inshore fleet emission rates of opacity of the vehicles, being directly related to the conditions of the lubricating oil thus contributing to reducing maintenance costs by contributing significantly to emissions of pollutants and an improvement in the air in large cities. This criterion was adopted and implemented, em 241 buses and produced a diagnosis of possible failures by the correlation between the characterization of used lubricating oils and the analysis of opacity, with the objective of the aid the detection and solution of failures for the maintenance of sub-systems according to design criteria, and for this to be a deductive methodology to determine potential causes of failures, has been automated to implement a predictive maintenance system for this purpose was used in our study a mobile unit equipped with a opacimeter and a kit for collection and analysis of lubricating oil and the construction of the network diagnostics, we used a computer program in Microsoft Office Access 2007 platform tool is indispensable for creating a database data, this method is being used and successfully implemented in seven (7) bus companies from the city of Natal (RN) Brazil / Este trabalho foi motivado pela import?ncia de realizar um estudo das emiss?es veiculares em frotas cativas com motoriza??o a diesel, associado ao plano de manuten??o preditiva. Esta modalidade de manuten??o engloba t?cnicas destinadas a atender a crescente exig?ncia do mercado em reduzir custos de manuten??o pelo aumento da confiabilidade dos diagn?sticos, o que fez crescer o interesse pelos sistemas automatizados de manuten??o preditiva nos motores a diesel, impedindo que problemas de rotina possam evoluir at? se transformarem em situa??es graves, solucion?veis apenas com repara??es complexas e dispendiosas, esta Manuten??o Centrada em Confiabilidade, ser? a metodologia que far? com que o objetivo seja atingido; al?m de manter os ve?culos regulados quanto ao consumo de combust?vel e emiss?o de poluentes. Para isso, estimaram-se melhorias t?cnicas capazes de penetrar no mercado automotivo e de conferir, nas frotas cativas, os ?ndices de emiss?o de opacidade dos ve?culos, sendo isso relacionado diretamente ?s condi??es do ?leo lubrificante, possibilitando a redu??o de custos de manuten??o, contribuindo de forma consider?vel com as emiss?es de poluentes e uma melhoria no ar das grandes metr?poles. Esse crit?rio foi adotado e implementado, em 241 ?nibus sendo produzido um diagn?stico das poss?veis falhas atrav?s da correla??o entre a caracteriza??o dos ?leos lubrificantes usados e a an?lise de opacidade, tendo como objetivo o aux?lio na detec??o e solu??o de falhas, visando ? manuten??o dos subsistemas segundo os crit?rios de projeto. Por ser esta uma metodologia dedutiva na determina??o de potenciais causas de falhas, foi automatizada para a implementa??o de um sistema de manuten??o preditiva; para esse fim foi utilizado nesse estudo uma unidade m?vel equipada com um opac?metro e um kit para coleta e analise do ?leo lubrificante; para a constru??o da rede de diagn?sticos foi utilizado um programa de computador em plataforma Microsoft Office Access 2007, ferramenta fundamental para a cria??o de um banco de dados, este m?todo est? sendo utilizado e implementado com sucesso nas sete empresas de ?nibus urbanos da cidade do Natal/RN, Brasil
2

An?lise das emiss?es atmosf?ricas por ve?culos automotores em Natal-RN

Brito, Herm?nio Pereira de 11 November 2005 (has links)
Made available in DSpace on 2014-12-17T14:58:11Z (GMT). No. of bitstreams: 1 HerminioPB.pdf: 3768069 bytes, checksum: 694372597a20b234c0403ab08b7bc801 (MD5) Previous issue date: 2005-11-11 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The fast urban occupation of Brazil, mainly from the last decade of 50, a sensible degradation of the quality of the air generated mainly for the activities was verified human beings associates to industrialization. From the past years, the situation has gotten worst in function of the increment of the fleet of vehicles in circulation in the great cities. Being these, in the city of Natal-RN, the ones that offer the biggest contributions to the atmospheric pollution. For atmospheric air to be a finite natural resources, indispensable and essential to the maintenance of the life in the land, is necessary to the implementation of action to improve its quality and to protect the health of the population. With the objective to study relative aspects to the characteristics of vehicles in use, the present study it searchs to analyze the levels of emissions of gases generated for vehicles converted bi-fuels into the modalities: natural gas (GNV), gasoline and alcohol, inspected for ends of register and together licensing to the State Department of Transit. One used the data gotten from inspections carried through for the company System Specialized in Inspection To propagate, in the city of the Natal-RN, capital of the State of Rio Grande do Norte, between 14 of November of 2003 and 30 of December of 2004. The analyzed parameters are established in the resolution n? 07/93 CONAMA. Of a total of 1.517 inspected vehicles, a average of 15,2% of failed was gotten, or either, that they emit levels of pollution above of the limits established for the legislation, below of the national average that is of 20,0%. The analysis of the data discloses that 7.3% of the fleet are converted the GNV; the growth of vehicles converted the GNV into the city is gradual, with a average of increment in last the 4 years of 23,3%; it has a vehicle predominance that has as combustible original to the gasoline (88,2%); the inspected fleet has average age of 8 years of use, considered young for the Brazilian standards, except for the moved one to the alcohol (average of use of 15 years). Moreover, the type of fuel is not the main parameter to define the indices of emissions; the age of the fleet is the parameter most important when emission is analyzed to propagate; the gas that more generates failed in the inspections is the corrected carbon monoxide; the vehicles generate higher indices of emissions in idling for all the fuels; the presence of the catalyser was not reflected, as it expected, in the reduction of emissions of gases toxic, however when analyzed according to year of manufacture, it was observed that for the vehicles manufactured between 1997 and 2004, reduction of 46,0% in the failed of the vehicles equipped with catalyser was gotten. In conclusion, the fleet of the studied sample, in average terms, takes care of to the requirements of Resolution CONAMA n? 07/93. The results gotten for the present study can subsidize action of public administrations that aim at to the improvement and the maintenance of the quality of air in the city of Natal-RN, as, for example, to implant a net of monitoramento of the quality of air / Com a r?pida ocupa??o urbana do Brasil, notadamente a partir da ?ltima d?cada de 50, verificou-se uma sens?vel degrada??o da qualidade do ar gerada principalmente pelas atividades humanas associadas ? industrializa??o. Ao longo dos anos, esta situa??o tem se agravado em fun??o do incremento da frota de ve?culos automotores em circula??o nas grandes cidades. Sendo estes, na cidade de Natal-RN, os que oferecem as maiores contribui??es ? polui??o atmosf?rica. Pelo ar atmosf?rico ser um recurso natural finito, indispens?vel e essencial ? manuten??o da vida na terra, ? necess?ria ? implementa??o de a??es para melhorar sua qualidade e proteger a sa?de da popula??o. Com o objetivo de estudar aspectos relativos as caracter?sticas de ve?culos automotores em uso, o presente estudo busca analisar os n?veis de emiss?es de gases gerados por ve?culos automotores convertidos a bi-combust?veis nas modalidades: G?s Natural Veicular, Gasolina e ?lcool, inspecionados para fins de registro e licenciamento junto ao Departamento Estadual de Tr?nsito do Rio Grande do Norte. Utilizaram-se os dados obtidos a partir de inspe??es realizadas pela empresa Sistema Especializado em Inspe??o Veicular, na cidade do Natal, capital do Rio Grande do Norte, entre os dias 14 de novembro de 2003 e 30 de dezembro de 2004. Os par?metros analisados foram os estabelecidos na resolu??o n? 07/93 CONAMA. De um total de 1.517 ve?culos inspecionados, obteve-se uma m?dia de 15,2% de reprova??o, ou seja, que emitem n?veis de polui??o acima dos limites estabelecidos pela legisla??o, abaixo da m?dia nacional que ? de 20,0%. A an?lise dos dados revela que 7,3% da frota ? convertida a GNV; o crescimento da frota de ve?culos convertidos a GNV na cidade, ? progressivo, com uma m?dia de incremento nos ?ltimos 4 anos de 23,3%; h? um predom?nio de ve?culos que t?m como combust?vel original a gasolina (88,2%); a frota inspecionada tem idade m?dia de 8 anos de uso, considerada jovem para os padr?es brasileiros, exceto para a movida ? ?lcool (m?dia de uso 15 anos). Al?m disso, tipo de combust?vel n?o ? o principal par?metro para se definir os ?ndices de emiss?es; a idade da frota ? o par?metro mais importante quando se analisa emiss?o veicular; o g?s que mais gera reprova??o nas inspe??es ? o mon?xido de carbono corrigido; os ve?culos geram ?ndices mais elevados de emiss?es em marcha lenta para todos os combust?veis; a presen?a do catalisador n?o se refletiu, como se esperava, na redu??o de emiss?es de gases t?xicos, por?m quando analisado segundo o ano de fabrica??o, observou-se que para os ve?culos fabricados entre 1997 e 2004, houve uma redu??o de 46,0% nas reprova??es dos ve?culos equipados com catalisador. Em conclus?o, a frota estudada em m?dia atende as exig?ncias da Resolu??o CONAMA n? 07/93. Os resultados apresentados no presente estudo podem subsidiar a??es de gest?es p?blicas que visem ? melhoria e a manuten??o da qualidade do ar na cidade de Natal, como, por exemplo, implantar uma rede de monitoramento da qualidade do ar

Page generated in 0.0834 seconds