Simulation Analysis And Isolation Performance Of Powertrain System

With the continuous advancement of science and technology,people's living standards have also been greatly improved.People have higher and higher requirements for vehicles as a means of transport.The ride comfort of the car has received more attention from consumers.The vibration of the powertrain is one of the main sources of vibration and noise of the entire vehicle,affecting the NVH level of the vehicle and the driving experience of passengers.Therefore,more automakers have increased their investment in capital and personnel in this area to increase the service life of auto parts and improve the NVH performance of the vehicle.A well-designed powertrain suspension system can improve the ride comfort and ride comfort of automobiles,and it is also a key content of vehicle development technology.This paper focuses on a light truck as the research object,and analyzes the vibration isolation performance of the powertrain mounting system.First,it reviews the development history of the powertrain mounting system and the vibration isolation components.It also briefly introduces the function and design requirements,decoupling theory and vibration isolation principle of the suspension system.Introduce several system decoupling methods and compare their advantages and disadvantages.Simplify the powertrain mounting system and analyze the road surface excitation and engine excitation respectively.The results show that only when the engine excitation frequency is greater than the natural frequency of the system,the system can play a vibration isolation effect.Second,the powertrain mass,mass center position,and inertial parameters are obtained through a test method.According to some other related parameters provided by the manufacturer,a system simulation model is established in the View module of the multi-body dynamics software ADAMS and using a variety of different methods to verify the accuracy of the model built.Using its vibration module simulation,the inherent characteristics of the system,namely the system's first six natural frequencies and the corresponding modal energy,are obtained.The results show that the existing system has a higher degree of coupling with other directions in a certain number of modes,and the system needs to be further optimized.At the same time,the time-frequency domain simulation analysis of the system under different working conditions is carried out to verify the correctness of the constructed simulation model.Then,the ISIGHT and ADAMS integration methods of the optimization software and the parameter optimization method of the approximate model in the ISIGHT were used to optimize.The second-generation non-inferior sorting genetic algorithm(NSGA-II)in the multi-objective optimization algorithm was selected.The mounting stiffness,damping,and installation angle were used as design variables,and the system anisotropy was used as the target variable,and related constraints were set.At the same time,the Insight module in ADAMS was used to analyze the sensitivity and guide the optimization results.The comparison and analysis of the results of the two methods ultimately selected the results of the integration method as the optimal design.The simulation results were used to compare the results before and after the optimization to verify the optimization results.Finally,the test methods for suspension vibration isolation and evaluation methods are elaborated.Through actual vehicle test methods,signal acquisition and related post-processing were performed on the top and bottom of the suspension before and after optimization and other locations of the vehicle,and the feasibility of an optimized design scheme was compared and verified.