Structral Performance Analysis And Optimization Of A Mini-electric Vehicle Frame

The maturity of CAE have allowed finite element method to been widely used in machinery, automobile and other industries and have made great achievements. The FEM has important meaning in improving the vehicle dynamic and static performance, optimizing the body and frame structure design, reducing vehicle development cycle. The application of FEM in automobile's structural design analysis, putting forward the improvement comments, and enabling the structure to satisfy the intensity and the rigidity request, have already become the important component in automobile designing. As the carrier of many important assemblys, the automobile frame withstands all kinds of complex load function from the path and loading. The reasonableness of its design directly concerns that whether the design of whole vehicle is successful or not. How to design reasonable frame has already become one of important contents of modern automobile design.This article takes a miniature pure electric automobile as the object of study, comprehensively utilizes three dimensional modeling technology, the finite element method and the structure optimization theory to make the general performance simulation analysis to the electric car frame. Firstly,based on the simplification of the frame and the loading, the finite element model was built by Pro/E. According to the driving characteristics, based on the finite element technique it uses the MSC.Patran/Nastran to take the static analysis of frame in four types of typical operating conditions to obtain the frame of the static stress and strain distribution. Secondly, it takes modal analysis and frequency response analysis to the frame, to identify the frame's natural frequency and natural mode, extract the dynamic displacement response under the frequency excitation of the key parts of the frame and determine the performance parameters of the frame, so that it makes us have a more comprehensive and objective understand to the performance of frame, provides evidences to the distribution of beam number, location and the strengthening of longitudinal mode. Finally, An optimization solution was put forward based on the generalized analysis result, take the frame quality as the goal carries on the section optimization and the whole improvement design. Then study of the new frame.This article showed this miniature pure electric automobile satisfy the intensity and the rigidity request, dynamic characteristics also meet request, But there is material wast and weaknesses. After optimization, the new frame is lighter than the original frame structure, utilization ratio of material was improved. It has provided the reference basis for the frame structure statics and dynamics analysis simulation and had the very important construction value to study the same frame and set standards.