Research And Optimization Of Torsional Vibration Model Of Automotive Powertrain

In recent years,with the continuous upgrading of automobile market consumption and the deepening of people's understanding of automobile culture,multi-purpose vehicles are favored by consumers with their advantages.At the same time,people's requirements for car ride comfort are constantly increasing.Automobile vibration and noise have always been the concern of production enterprises and engineers.Multipurpose vehicles have attracted the attention of manufacturers and engineers because they are more likely to cause vibration and noise problems.Therefore,it is necessary to establish a model for torsional vibration control of the powertrain of this type of vehicle.In this paper,aiming at the interior roar caused by torsional vibration of a frontdrive and rear-drive vehicle's powertrain,the simplification process of the model is studied,the centralized mass model of the system is established,and then the model is simplified.Finally,some torsional vibration optimization methods based on the simplified model are put forward and the feasibility of the optimization schemes are verified.The main contents are as follows:Firstly,the torsional vibration of the powertrain of the vehicle is tested for the roar problem in the vehicle.Then,according to the principle of the equivalent torsional vibration system of the powertrain,the components of the powertrain are simplified and modeled.Finally,a 19-degrees-of-freedom centralized mass model of the powertrain is established.Secondly,based on the theory and method of torsional vibration characteristic analysis,the simulation models of free torsional vibration and forced torsional vibration are established in AMESim software,and their torsional vibration characteristics are analyzed.Finally,the simulation and experimental results are compared and analyzed to verify and improve the model.Thirdly,on the basis of the original model,aiming at modal analysis and torsional vibration response analysis respectively,the original model is simplified and merged into 6-degrees-of-freedom free torsional vibration simulation model including engine,transmission,transmission shaft,driving axle,wheel and body,and 13-degrees-offreedom forced torsional vibration simulation model.The simulation results of the simplified model are compared with the actual experimental results and the original model simulation results respectively.The results show that the simplified free torsional vibration model and forced torsional vibration model are effective.Finally,on the basis of the simplified model,taking the clutch stiffness influence law analysis as an instance,the influence law analysis of the parameters in the power transmission system is carried out respectively,and the parameters which have tremendous impact on the torsional vibration amplitude of the power transmission system are found out.Then,according to the variable range table of the transmission system provided by the enterprise,a single-parameter and multi-parameter adjustment scheme for these parameters with maximum variation range is proposed.Then,the optimization scheme of torsional vibration with elastic coupling and torsional shock absorber is put forward,and the optimization effect is remarkable.