Object-oriented Modeling And Simulation For Engine System Dynamic Studies

The market demand for greater vehicle performance, coupled with the increased regulatory requirements on emission level and fuel economy have caused increasing performance of engine which is regarded as heart of vehicle. The trend makes researching and improving performance of engine more and more important. In this paper, basing on object-oriented technology, modeling and simulation of engine dynamic system has been studied.First, modeling language and method of system dynamic analysis has been put forward. Through introduce two modeling language which have been widely applied in engine dynamic simulation system at present such as process-oriented structure language and object-oriented physical system language, object-oriented modeling method is represented in full. With the method, according to the principle of independence and physical integrality, Dymola/Modelica has been utilized as a programming environment and engine component library which can reusable and extend is set up. Then following reality constituent of engine and connecting component interface, a nonlinear signal cylinder engine model has been created, though fire interval and fire order, a control-oriented four cylinders engine is build. Following dynamometer is seen as load, performance of engine is simulated and researched under the condition of constant torque and speed, validation of the math and simulation model have been confirmed by comparison result between simulation with test result of engine performance simulation software Dyno. In the end, powertrain is constituted by gearbox model,chassis model and engine model, application of nonlinear engine model in IPC(Integrated Powertrain Control) is illustrated.