Abstract: In order to improve the vibration isolation performance of exhaust system of a certain model,the finite element model of exhaust system was constructed with HyperMesh softwore and analyzed for vibration isolation performance. After testing and analysis, the transfer force is too large, the sum of the transfer force and the standard deviation of each ear were reset as the optimization target 1; and the sum of static displacement of each ear and the standard deviation of preload force were taken as the optimization objective 2. In HyperStudy softwore,the Z-direction stiffness of the six lifting lugs was finally determined by Latin hypercube sampling and DOE variable screening,and the response surface model was constructed,and the optimal lifting lug stiffness value was obtained by Multi-Objective Genetic Algorithm (MOGA). The best lifting lug stiffness value was brought into the finite element model of the exhaust system for further analysis,and the results show that the optimization target was improved. Finally,the actual production of lifting lugs was tested on the actual road after loading,and the test results show that the vibration isolation rate is greater than 20 dB, which is the same as the finite element result,which meets the production design requirements.

Key words: exhaust system, Latin hypercube, Multi-Objective Genetic Algorithm(MOGA), vibration isolation rate