Desempenho de sondas Lambda no monitoramento de motores do ciclo Otto alimentados por etanol e GNV

• Ano de defesa: 2015
• Autor(a) principal: Cruz, César Roberto [UNESP]
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Estadual Paulista (Unesp)
• Palavras-chave em Português: Oxido de zirconio; Detectores; Oxigenio; Stents (Cirurgia); Etanol; Zirconium oxide
• Link de acesso: http://hdl.handle.net/11449/132500; http://www.athena.biblioteca.unesp.br/exlibris/bd/cathedra/18-12-2015/000854863.pdf

With the increasing number of motor vehicles in circulation, the amount of pollutantos released in the atmospheric air is very significant, being a real disk to our planet. People concerned about the consequences resulting from his problem have charged effective actions in order to minimize the impact of polluent generated and the preservaton of the life quality on our planet. Significant technological advances have been made in recent years, both in the forms of propulsion, when on reducing emissions by engines. The development and adoption of new materials, both in construction, or in the control of the several systems, is one of the bases of this major development. Among these materials, the ceramics have played a very important role in this scene, whose applications are enabling the achievement of the proposed objectives. This work focuses primarilly about the oxygen sensor using zirconia (ZrO2) as basic element. Also known as lambda sensor, it is used in automobiles to control along with the electronic management system of the engine, of air-fuel ratio, in orderto reduce the emissions and the fuel comsumption in internal combustion engines of Otto and Diesel cycles. It is installed in the exhaust gas system and aims to measure the residual oxygen content in gases produced by the engine. In this work we analyzed the performance of these sensors in measuring the concentration of residual oxygen content in the exhaust gases when installed on an Otto cycle engine, 4 stroke, endowed with electronic multi fuel management system (Tetrafuel), installed independently to the vehicle on a test bench, operating distinctly with liquid fuel (ethanol) and gas (CNG), in two predefined speeds. In this work, we will present is composition, construction, operating principles and performance in a real operating situation, of four sensors of different manufacturers allowing the understanding of its interaction with the electronic management system and the...