The Vibration Analysis And Structural Optimization Of Rubber Mount For Automotive Engines

The engine rubber suspension system can effectively isolate the vibration and noise generated by the engine,protecting the driver and passengers from the impact.However,modern car designs tend to be lighter and more powerful engines.These two trends also have a bad effect on vibration isolation performance.The suspension element is in an extremely important position on the vibration transmission path of the vehicle.Design a powertrain suspension system with good vibration isolation performance,which can not only effectively isolate the transmission of engine vibrations to the vehicle body,improve the ride comfort of the vehicle,but also can suppress the impact of road unevenness excitation on the engine and improve the work reliability of the powertrain.,so matching and optimization the engine mount system plays an important role in improving the NVH performance of the vehicle.Nowadays,when many companies adjust the NVH performance of vehicles,they still select the rubber mount that meet the vibration isolation requirements through trial and error.This method lowers Rubber Mount design efficiency.In this paper,by consults many theses on rubber mounts at home and abroad,an engine rubber mount system is considered as the research object,and vibration analysis and structural size optimization of the engine rubber mount system are performed.The main research contents include:(1)A multi-rigid-body dynamics software ADAMS was used to establish a simulation model for the rubber mounting system of the engine and analyze the intrinsic characteristics.It was checked whether the suspension system was unreasonable in terms of decoupling ratio and natural frequency matching.In view of the irrationalities in the system,the stiffness of the three directions of the three suspensions is taken as the design variable,and the maximum energy decoupling ratio in the vertical directions are the target,then optimize the original mount.(2)Based on the ABAQUS,the finite element simplification model of the suspension element is established.The geometric parameters with large influence on the threedimensional stiffness of the suspension are selected as the variables in the optimal Latin square test design method.The mounts with different parameters are calculated in the ABAQUS software.The stiffness is used to establish a sample point of the relationship between the suspension dimensions and stiffness.Based on the sample points,ISIGHT software was used to establish approximate models of rubber mount systems with different methods and analyze the accuracy of each approximate model.Finally,the most accurate approximate model was selected to replace the finite element analysis model.(3)Based on the above-mentioned approximate model,the rubber suspension elements are optimized using the NLPQL method to obtain a rubber mount geometry that satisfies the stiffness requirements.The article mainly adopts a combination of forward optimization and reverse design.Using an approximate model instead of a finite element model.It quickly designs specific structural parameters of rubber suspension that meet the target stiffness.This method overcomes the difficulties to select suspensions that meet vibration isolation requirements through repeated trial and error and has a certain reference value in engineering.