Optimization Design And Research Of A Passenger Car Body With Light-weight As The Target

The development of automobile industry in the world is facing three major themes: energy saving, environmental protection and safety. Automotive light-weight is one of the important ways and means that achieving energy conservation and emissions reduction, which has very important significance for the sustainable development of the whole automobile industry.This thesis analyzes the light-weight of automobile from different perspectives which based on the summary of the background and technology about the light-weight automobile in domestic and overseas. Firstly, the previous modeling of finite element analysis is based on CATIA, the modeling process strictly follows the engineering model specifications. Then, the analysis of foundation model including normal modal analysis about the dynamic properties, bending and torsion stiffness of BIW, nodes stiffness and mounting stiffness analysis shows that there is abundant space for the light-weight meeting requirements. Then, through the sensitivity analysis about the quality, bending and torsion stiffness of the light-weight automobile finds out the mechanical components of a high influence on its performance. Finally, combining the optimization of the mounting stiffness updates the structures of BIW to compare the performance parameter of before and after optimization.Through the optimized analysis of the body structure, the BIW successfully lost weight of 8.55 kg and achieved the aim of the light-weight automobile meeting requirements about modal, stiffness and strength.