Vibration Reduction Research And Optimization Of Powertrain Mounting System

The powertrain mounting system vibration reduction performance has a great influence on the performance of NVH.Exploring the dynamics response of powertrain and reasonable optimizing the mounting system are of great significance to improve the decoupling degree and the passengers' comfort.In this paper,a model for powertrain mounting system is built as the research object.Each order modal energy decoupling degree built as the objective function in the idle condition is optimized,then more reasonable stiffness parameters of the mounting system is obtained for the vibration reduction effect.Based on Lagrange vibration differential equation,the dynamic simulation model is established.In order to conclude the damped plays an important role in the mounting system,the damped and undamped mounting support reaction were analyzed under the idle condition.Through the rated conditions and maximum torque working condition of the reaction force and the center of mass around the angular acceleration response of the rolling shaft further verify that the idle condition is the typical analysis condition.Under the idle condition for the analyzed calculation,the system natural frequency and energy distribution can be got.Then each round of reaction force and dynamic assembly of rolling shaft angular acceleration amplitude frequency characteristic curve for powertrain mounting support also can be obtained.The relationship between the system natural frequency and the working frequency are obtained.With mounting stiffness parameters as design variables,scope of mounting stiffness as constraint conditions and each order modal energy decoupling degree as the objective function,a series of experimental design and optimization analysis are used under ADAMS/Insight module.In the end,stiffness of the optimized parameters will be work out.Based on the principle of double layer vibration isolation of the powertrain vehicle model,the vibration transmissibility could be solved.In time domain and frequencydomain analysis before and after optimization of contrastive analysis and vibration transmissibility curve line,it is concluded that the optimized fluctuation amplitude of mounting support reaction and vibration transmissibility reduced.System's inherent frequency allocation becomes more reasonable,and the decoupling degree rise generally,achiving the vibration reduction effect.