Dynamic And Static Performance Analysis And Lightweight Research Of Car White Body

With the development and popularization of CAE,the finite element analysis has become an important part of the car designing.No matter in the remodeling of cars,or the developmental stage of new models,using the finite element method(fem)to analyze and optimize the structure of cars can improve the designing quality,shorten the developmental cycle,and save the developmental costs.This thesis will example the white body of a certain domestic type automobile as the research object,analyzes and studies the dynamic and static performances and the light weight fabrication of the structure of the white automobile.Based on the theory of finite element,establishes the finite element model of the white body,and uses the finite element software to analyze the modality and stiffness of the structure of the white body.The modality analysis for white body will get the frequency and vibration mode of the first 10 steps,the higher the modality frequency,the more balanced and reasonable the distribution of the vibration mode,and there is no resonance phenomenon.Stiffness analysis of the structure of the white body can get the value of the bending stiffness and the torsional stiffness.Compared with the reference value of the stiffness the same type automobile abroad,the bending stiffness of the white is slightly insufficient,and the torsional stiffness is up to the standard.Using the principle of sensitivity analysis,on the basis of the structure stiffness and the modality characteristics of the white body,this thesis will calculate the first-step torsional modality,the first-step bending modality,and sensitivity values of the bending stiffness and torsional stiffness of component thickness of the white body.Through the calculation of the relative sensitivity,this analysis will introduce the definition of the synthetical relative sensitivity.The definition considers the relationships of the body bending stiffness,the torsional modality,the quality of the automobile body and the sensitivity of the thickness of the parts,which can efficiently and synthetically screen out the "appropriate" optimal artifacts.Combining with the theory of the optimization design,using the method of size optimization designing,and regarding the thickness of the components as design variables,this thesis will analyze the lightweight of the structure of the body.Compared with the original model,the dynamic and static performances of the readjusted structure of white body have been improved,and the lightweight effect is obvious.