Simulation And Optimization Of Vehicle Powertrain Mounting System

With the development of science and technology,the automotive industry is growing up rapidly worldwide,its technology and performance are constantly improving,as a convenient way for people to travel,automobile plays an indispensable role in people's work and life,and the vehicle ride comfort as an important measure of automobile quality comprehensive index,by the wide attention of consumers.The engine powertrain mounting system is one of the main sources of automobile vibration noise,which has a direct and important influence on the ride comfort of the occupants.Reasonable design of the suspension system can not only effectively isolate the vibration of the powertrain and the impact caused by road roughness,but also extend the service life of the engine and its parts.In this paper,the engine powertrain mounting system of a passenger car is taken as the research object.After the experiment is carried out,the relevant data are collected and simulated by ADAMS software.The shortcomings of the suspension system are optimized.The main work is as follows:1.By consulting a large number of references,this paper analyzes the development status of the powertrain mounting system at home and abroad,and studies the isolation problem of the engine from the engine vibration isolation principle of single freedom system.The arrangement of the mount is analyzed,and the inertial product of the powertrain mounting system and the stiffness data are measured through experiments.2.In the ADAMS software to establish six degrees of freedom dynamic model of suspension system using the Vibration module on the suspension system for the simulation calculation,getting the system of six order modal natural frequencies and corresponding energy decoupling rate,and with the MATLAB software to establish the mathematical model,comparing the calculation results based on the analysis of modal frequency and decoupling rate and to evaluate existing suspension system.3.The finite element model of the suspension system is established in Hyper Mesh,and the suspension system is simulated by ABAQUS software.Based on the loading conditions of North American General Motors,the dynamic assembly mass and the elasticity of the suspension element under typical operating conditions are calculated The displacement and the suspension force of the center,and the strength of the suspension bracket is checked to verify the design of the suspension rigidity and the suspension bracket.4.According to the actual situation of the project,the stiffness parameter of the suspension element is used as the design variable to improve the vibration decoupling rate of the suspension system as the optimization target.At the same time,the reasonable matching of the natural frequency of the powertrain suspension system and the range of stiffness of suspension element is the constraint condition.The nonlinear function fgoalattain in MATLAB is used to optimize the parameters of the suspension system,and the optimized parameters are substituted into the multi-body dynamics software.Results are compared with the simulation results before optimization,the decoupling rate is improved to achieve the desired goal.