The Finite Element Analysis Of A Body Frame Based On ANSYS And Its Light-weighting

As the main bearing structure of the vehicle,the strength,stiffness and dynamic characteristics of the body frame have a crucial impact on the safety performance and service life of the vehicle.However,the stress condition of the body frame is more complex,and the structural analysis is more difficult.To solve such problems,researchers used a variety of methods to calculate.Finite element analysis method is one of them.Skeleton of a car body is taken as the research object in this paper.The static analysis,modal analysis,random vibration analysis,fatigue strength calculation and lightweight research of the structure are carried out by using the finite element analysis method,which provides reference and basis for the parametric design.The static analysis of the body frame under four working conditions of bending,turning,emergency braking and ultimate torsion is carried out,stress distribution and deformation of structure is obtained,the analysis results show that the static structure performance of the body skeleton meets the requirements for use,which provides the basis for lightweight research.The modal analysis of the body frame is carried out,obtaining its first ten orders natural frequencies and modal shapes,which is compared with the frequency range of road excitation the body frame,the analysis results show that the car has good dynamic characteristics,and the stress and deformation of the structure and engine excitation,to lay the foundation to avoid resonance and subsequent dynamic analysis.Based on the results of modal analysis,The modal superposition method is used to analyze the random vibration of the body frame,and the stress and deformation of the structure are obtained.According to the calculation results of random vibration,and random fatigue strength calculation on the body frame structure is conducted by Three interval method,and the reliability of the fatigue strength of the body frame under random excitation is verified.According to the calculation results of static analysis and modal analysis,the lightweight of body frame is studied.The lightweight aluminum alloy material is used to replace the raw material.On the basis of ensuring the safety performance of the body frame,The weight loss of skeleton was 253 kg,and the weight loss rate was 26%.,which proves the feasibility of the lightweight scheme.