A Study On Combustion Process And Parameters Optimization Of 495 Dissel Engine

The working process of diesel engine involves gas-liquid flow, fuel injection, combustion of the working fluid, heat transfer, mass transfer, chemical reaction dynamics and other integrate physical processes. Its performance mainly depends on fuel injection and air supply and flow patterns.These complex factors affect each other, influence dynamic performance,economy performance, emission performance etc. With the rapid development of science and technology, computer simulation technology has been widely used in engine design and improvement. Compared with the traditional engine design, research methods, by using the computer numerical simulation can not only save manpower and material resources, decrease research expenses, shorten engine development cycle, but also gain some parameters that can not be obtained from experiment.In this paper,AVL BOOST software were used to establish simulation model of 495 diesel engine to simulate the work process,and studying the influential parameters of engine.According to the diesel engine work process thermodynamic basis and calculation principle of BOOST soft,builds up the simulation model of 495 diesel engine, then verifies the accuracy of the model through compare the simulated results and experimental results. Based on the diesel engine model,the engine's speed characteristics at each revolving speed were simulated, at the same time.the influence of exhaust system,valve timing,compression ratio,injection advance angle on diesel engine were analysed.Then, the optimum engine working parameters were determinedBased on the optimized working parameters of diesel engine,the simulation of 495 direct injection diesel engine are carride out again,the analog simulation results and the original engine in power, economy and emission performance aspects are compared and analyzed.The results shows that choose the optimum distribution phase, compression ratio, injection advance angle not only can improve the combustion process in cylinder,but also enhance engine's dynamic performance,economy performance, decrease fuel consumption etc. In summary, the use of computer simulation technology can to provide theoretical guidance for designing and improving the engines, shorten the test cycle and reduce development costs.