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Abstract(s)
A simulação do comportamento de máquinas, em geral, e de motor de pistão, em particular (combustão interna), é muito importante para que se possa prever o seu funcionamento, mesmo antes da fabricação, bem como os problemas que possam prejudicar sua operação. Isto resulta numa redução significativa nos custos de desenvolvimento e na antecipação do início da produção. O modelo Honda GX35 é apresentado neste trabalho para a simulação numérica do funcionamento de um motor de pistão, operando nos ciclos Diesel ou Otto, de dois ou quatro tempos, naturalmente aspirados ou turbo alimentados, com qualquer número de válvulas, dutos, junções.
Para efeito de simulação, o motor é dividido em elementos: câmara de combustão, cárter, duto, carburador, junções, abafadores de ruído, etc. Para cada um desses elementos é possível desenvolver um modelo numérico. O desempenho do motor é obtido através da aplicação das leis de conservação a cada elemento e da compatibilização das propriedades do escoamento nas interfaces de elementos adjacentes, resolvidas através de um programa computacional.
Os padrões de segurança dos motores e a fiabilidade envolvida no fabrico dos seus componentes são de elevada exigência. No caso particular de peças integrando o motor (geralmente de combustão interna), o sucesso do bom desempenho em serviço depende de apurada investigação. Neste trabalho foi selecionado o estudo da simulação numérica do funcionamento de um motor de pistão. Para este projeto, foi efetuada simulação numérica a partir de software dotado da componente teórica necessária à caracterização do campo de temperaturas.
As situações consideradas referem-se ao caso de combustão dita normal e com detonação, em que aqui o regime de pressões e temperaturas é muito severo, afetando a curto ou médio prazo a duração e integridade do componente.
The simulation of the behavior of machines in general, and piston engine in particular (internal combustion), is very important so that it can be foreseen its operation, even before manufacturing, as well as the problems that may hinder its operation. This results in a significant reduction in development costs and in anticipation of the start of production. The Honda GX35 model is presented in this work for the numerical simulation of the operation of a piston engine, operating in two or four stroke, naturally aspirated or turbocharged Diesel or Otto cycles, with any number of valves, ducts, joints. For simulation purposes, the engine is divided into elements: combustion chamber, sump, duct, carburetor, junctions, noise damper, etc. For each of these elements it is possible to develop a numerical model. The performance of the motor is obtained through the application of conservation laws to each element and the compatibility of the properties of the flow in the interfaces of adjacent elements, solved through a computational program. The safety standards of the motors and the reliability involved in the manufacture of their components are of high demand. In the particular case of parts integrating the engine (usually internal combustion), the success of the good performance in service depends on investigation. In this work the numerical simulation of the operation of a piston engine was selected. For this project, numerical simulation was performed from software equipped with the theoretical component necessary to characterize the temperature field. The situations considered refer to the case of normal and detonated combustion, in which the pressure and temperature regime is very severe here, affecting in the short or medium term the duration and integrity of the component.
The simulation of the behavior of machines in general, and piston engine in particular (internal combustion), is very important so that it can be foreseen its operation, even before manufacturing, as well as the problems that may hinder its operation. This results in a significant reduction in development costs and in anticipation of the start of production. The Honda GX35 model is presented in this work for the numerical simulation of the operation of a piston engine, operating in two or four stroke, naturally aspirated or turbocharged Diesel or Otto cycles, with any number of valves, ducts, joints. For simulation purposes, the engine is divided into elements: combustion chamber, sump, duct, carburetor, junctions, noise damper, etc. For each of these elements it is possible to develop a numerical model. The performance of the motor is obtained through the application of conservation laws to each element and the compatibility of the properties of the flow in the interfaces of adjacent elements, solved through a computational program. The safety standards of the motors and the reliability involved in the manufacture of their components are of high demand. In the particular case of parts integrating the engine (usually internal combustion), the success of the good performance in service depends on investigation. In this work the numerical simulation of the operation of a piston engine was selected. For this project, numerical simulation was performed from software equipped with the theoretical component necessary to characterize the temperature field. The situations considered refer to the case of normal and detonated combustion, in which the pressure and temperature regime is very severe here, affecting in the short or medium term the duration and integrity of the component.
Description
Keywords
Motor Pressões Rendimento Simulação