Finite Element Analysis Of Suspension Strut Mounting Based On Transfer Characteristics

With the rapid development of the domestic automobile market,people’s requirements for NVH performance of automobiles are gradually improved.As a device that transmits force and torque between the car body(or frame)and the wheels,the suspension plays a role in affecting the handling stability and ride comfort of the car.Based on the tensile test of rubber materials,this paper takes a passenger car as the research object,and does the following work around its vibration transmission characteristics:Firstly,based on the hardness of automobile suspension bushings rubber,uniaxial tensile test was carried out according to the national standard.The test results were used as data sources for constitutive model simulation analysis,and the influence of rubber hardness on tensile mechanical properties was studied by comparing the test results with the simulation results,as well as the accuracy of description of uniaxial tensile test results by several commonly used constitutive models.Then,on the basis of the determined constitutive model,the static and dynamic stiffness of the suspension support bushing was simulated,and the influence of rubber hardness on the static and dynamic stiffness of the suspension support bushing was analyzed.Secondly,the front and rear suspension parts including all rubber bushings were processed by finite element.The road roughness Simulink model was built,and the road height roughness was taken as the input load.The dynamic simulation calculation was carried out on the front and rear suspension to obtain the vibration acceleration values.After the conversion into the frequency domain,the influence of upper support bushing with different rubber hardness on the performance index parameters of Mc Pphson suspension and multi-link suspension was analyzed.Finally,all the rubber bushings were simplified as spring elements,and the whole vehicle was processed by finite element method.The modal frequency and modal shape of the body in white and the vibration transfer characteristics of the whole vehicle were calculated.Combined with the modes of the body in white and the suspension support bushings with different rubber hardness,the influences of the rubber hardness and the body in white mode on the vibration transfer characteristics of the whole vehicle were studied.According to the simulation results,reducing the rubber hardness of the suspension support bushing can improve the ride comfort of the vehicle to a certain extent.Based on suspension bearing bushing as a starting point,tensile test of rubber materials,and data for the reference to this model,this paper compares and analyzes calculation suspension bearing static and dynamic stiffness of the lining sleeve for the combination of different hardness rubber test data analysis,the influences of stiffness value,finally calculated the suspension assembly and vehicle vibration acceleration,The influence of rubber hardness on vibration transfer characteristics was analyzed.In the early stage of vehicle development without real vehicle,the vibration transmission of the vehicle can be obtained by simulation,and the ride comfort of the vehicle can be improved by directly modifying the rubber material of the suspension support bushing.