Research on Optimization Analysis Method of Exhaust System Under Multiple Loading Conditions

Abstract

The exhaust system is connected to the engine and mounted on the body-in-white with lifting lugs and rubbers. The vibration of the engine can be transmitted to the exhaust system through the bellows, which affects the NVH performance of the vehicle. Optimal design of the vibration isolation, the stiffness of the lifting lugs, the strength and other performance parameters should be taken into account. The exhaust system has many variable parameters, including the stiffness of the bushing, the shape of structure, the thickness of the exhaust pipes, and so on. It is difficult to find the optimal parameters of the exhaust system based on conventional method. In order to solve the problem, In order to solve the problem, the HyperWorks software was used to simulate the exhaust system. With HyperStudy, the DOE design method is used to create a response fitting approximate model, and the optimal solution is obtained by genetic algorithm. Then in the finite element model of the exhaust system, the size and shape optimization design were carried out to obtain the global optimal solution. The results revealed that this analytical method is practical and suggestive for multi-objective optimization analysis of exhaust system.