Optimization Design Of Key Parts Of Car Body

With the development of society, automobile as the main mean of transport gradually integrates into people's life and becomes a necessity, it makes people's life become fast, expands the scope of people's communication and gives people the convenience of travelling. However, nowadays, people's requirements on automobile is no longer stay in a simple means of transport, automobile should let people be safety whatever is inside and outside, make less consumption of resources, and also keep the effact on the environment as small as possible. It means that only the automobile gets more outstanding performance in safety, energy saving and environmental protection is to make automobile continue to play an important role in the future social development process. The concept of automotive lightweight is proposed accordingly. Automotive lightweight is now the major automotive companies and engineers racking their brains, devoting efforts to the main research direction.This thesis takes the domestic and foreign automotive lightweight situation as the background, combined with current lightweight technology, the lightweight design of a brand car is carried out. The performance of the white body weight reduction is achieved by taking the function of the white body mass as the objective, bending stiffness, torsional stiffness, first order mode, first order bending mode and first order torsional mode as the constraint condition.Firstly, the parametric finite element model is obtained by using SFE-CONCEPT software to carry on the implicit parametric modeling; And then the obtained parametric model is compared with the geometric model established by CATIA to verify the correctness of the parametric model; Finally, by using the method of full factor, orthogonal arrays, and optimal latin hypercube design to design experiments, the method of RSM and orthogonal to constucte approximate model, so the lightweight body with satisfied static and dynamic performance was abained by optimize the approximate model.According to the light weight coefficient, the light weight resulte of this thesis is evaluated, the lightweight coefficient before optimization is L0=5.92, and the final lightweight coefficient is Lt=4.90, the lightweight rate is 17.23%, which proves the lightweight method in this paper is feasible.