The Computer Simulation And The Parameters Optimization Of An Automobile Powertrain

The power train has great influence on automobile's power performance and economy performance, so its parameter is very important in the design of an automobile. In this paper, the optimization theory is used in the design of the power train in order to improve the performance of the automobile, and a suit of software about this is designed.Firstly, the paper discusses the tradition evaluation of the automobile's power performance and the economy performance, and investigates a series of comparable evaluation that estimate the automobile's power performance and economy performance synthetically. It can report the exerting degree of the automobile's performance between the real working station and the ideal working station of the engine, furthermore, it evinces the potence and the way to improve the power performance and the economy performance. Then summarizes the calculating methods of the power performance and the economy performance, which can be realized by the computer easily. introduces the mathematic model of the automobile power train.Based on this, uses the origin underway accelerate time and the oil consumption at the cycle of multi-working conditions as the objective functions of the power performance and the economy performance respectively,and then transforms it into a single objective function by using the linear adding. Establishing the optimization mathematical model between the engine and the power train of the automobile, lastly, solves it with the complex algorithm, which finding out the prime parameter of the power train to improve the integer performance of the automobile.Based on above theory, uses VB(Visual Basic) and Matlab as a tool to develop the software of the transmission parameters optimization, it has a very friendly interface, and can be operated easily. Except the optimization function, the software also can calculates the power performance and the economy performance of the automobile.At the end of the paper, the author uses the software to calculate by the example of Lubao HFJ7110 car, then analyses the result which shows the feasibility and the practicality of the software. At last the author gives some pieces of advice to go on working on this object.