Structural Optimization Of Powertrain Rubber Mount

Rubber material is more and more widely used in automobile damping device because of its good vibration isolation ability.However,the performance failure of this kind of damping device due to fatigue damage will seriously affect the ride comfort and safety of the vehicle.Therefore,it is of great significance for automobile industry to effectively improve the fatigue life of rubber damping device.In this study,the powertrain rubber mount is taken as the research object,and the fatigue life of the rubber mount is improved by structural optimization.In this study,a set of optimization method for powertrain rubber mount structure is proposed by combining theoretical analysis,finite element simulation analysis and actual test.This method can optimize the structure of mount new products in the development stage,and greatly reduce the optimization cost in the later stage.Firstly,the basic mechanical properties of rubber materials were tested to obtain the necessary constitutive model parameters for finite element simulation.The three-dimensional model of rubber mount is established on Unigraphics NX software,and the finite element simulation of the model under the ultimate load is carried out with Abaqus software to obtain the position of the joint prone to failure and the corresponding fatigue damage parameter value of the joint.Then,the fatigue life prediction model of rubber material is established based on the fatigue test results of rubber dumbbell shaped test column,and the fatigue damage parameters obtained by finite element simulation are substituted into the prediction model to obtain the fatigue life prediction value of rubber mount.The accuracy of the fatigue life prediction model is verified by comparing the predicted value with the measured fatigue life of rubber mount.Finally,the structural parameters of the rubber suspension model are adjusted,and the finite element simulation results of the adjusted model are combined with the fatigue life prediction model to obtain the influence of various structural parameters on the fatigue life of the rubber suspension.Then,using the established static stiffness prediction model of rubber mount,the influence of structural parameters on the static stiffness of rubber mount under load is obtained.On this basis,the orthogonal test method is used to optimize the structure of rubber mount.The fatigue life of the rubber mount after optimization is increased by27.9% compared with that before optimization,and the Y-direction static stiffness is basically unchanged,which verifies the feasibility of the structural optimization method,and provides a guidance method for improving the fatigue life of rubber vibration damping products.In this study,a set of methods is proposed to improve the fatigue life of the powertrain rubber mount by optimizing the structural parameters,and keep the static stiffness of the load direction unchanged,which provides a reference for the performance optimization of other rubber vibration damping products with different structures.