Stiffness Analysis And Structure Optimization Of Car Body

The stiffness analysis of car body leads to optimization of car body. Most modern car bodies use bearing structure. This kind of structure can meet most requirements, like structure lighting, steering stability and manufacturability etc. This kind of car body endues most loads of the car including torsion and bending. Unreasonable stiffness of car body will directly influence a number of important performance such as the reliability and endurance of structure, safety, steering stability, performance of NVH, fuel consume, lighting of structure, airproof of car body, static and dynamic characteristics of car body etc.The aim of optimization analysis of car body stiffness is to improve the stiffness of the whole car, and to meet the design requirements of the car. At the same time, it also may improve the vibrating characteristics of car body, at the large extent reduce the whole weight of car body, and solve the problems of car body lighting.In this paper, the stiffness characteristic of A0 car body is analyzed and the optimization method is discussed. After introducing the mathematical model of body lighting and the basic theories about structural sensitivity analysis, the body lighting strategies and processes are discussed. On this basis the finite element model of car body is established and the structural sensitivity is analyzed. An optimization result of the car body shows that the total mass has been reduced by 3.37%, while the stiffness and natural frequency rise to different degrees. It is therefore indicated that the sensitivity analysis as the basic of the body structure modification is an effective approach to improving the NVH performance of car as well as body lighting.