Design Calculation And Optimization Of The Commercial Vehicle Powertrain Mounting System

Automobile vibration and noise are important indicators of automobile comfort,and with the continuous development of economy and society,higher comfort requirements are required by people.Through the reasonable optimization design of the powertrain mounting system,the vibration and noise transmitted from the engine to the body can be greatly reduced.In this dissertation,the powertrain mounting system of a commercial vehicle is taken as the research object.Firstly,the inertia parameters of the powertrain are measured by using the trilinear pendulum;then the powertrain mounting system is modeled,and each order of inherent frequency and energy decoupling rate in each direction of the powertrain mounting system are simulated by using MATLAB,and the results are verified by using ADAMS.The results show that the MATLAB and ADAMS calculation results are basically consistent.Then,the multi-objective optimization of the decoupling target,dynamic reaction force and the sum of each frequency interval is carried out based on the NSGA-II algorithm,and the optimization results are analyzed for robustness.The correctness of the optimization method is proved through the vibration isolation test of the whole vehicle powertrain mounting system.The 28 working conditions of the mounting system are analyzed according to the optimization results,and the strength of the mounting bracket is calibrated by the calculation results.Finally,for the stiffness design requirements of a bushing-type rubber mounts,the non-rubber filled structure of the mounts is optimized,and the orthogonal experiment combined with ABAQUS finite element software is adopted to simulate the stiffness of the rubber mounts.Based on the experimental results,a second-order response surface model is established and optimized by Sheffield genetic algorithm to obtain the parameters of the non-rubber-filled structure to meet the mounting stiffness requirements.The research results of this dissertation are useful as a guide for the design and development of powertrain mounting systems for commercial vehicles.