The Virtual Test Research On Automobile Crash Safety

Automobile crash safety is a big and serious problem for world-wide automobile industry to solve now. Not only did the traffic accidents take great economical loss to the society, but also killed millions of passengers every year. One of the most important ways of protecting people from being hurt or killed in an accident is improving vehicles' crashworthiness. In order to enhance vehicle's crash safety performance, there is an urgent need to design proper automobile structure, which makes people survive when the vehicle is destroyed and lets people not hurt when the vehicle is damaged in a traffic accident .As a result, improving automobile crashworthiness has become the important topic of various countries' automotive industry.Virtual test approach is applied in the modern automobile designing progress extensively. The Finite Element Analysis (FEA) method, which is one of the most important ways of virtual test, can be used to calculate the crashworthiness and predict the safety of the vehicle. In the thesis, the author took a minibus as an example. Firstly the FEA model of the minibus's BIW was established according to the geometry model of the full scale vehicle, and the model could be a foundation of automobile crash simulation next. Then the strength analysis simulation of the BIW was done considering four typical operation situation.Based on the simulation result, we established frontal crash FEA model, set up the analysis loadstep due to GB11551-2003 and calculated the model by computer. Comparing with the crash experimental test of real car, the simulation had the same results basically, which proved that the computer simulation upon the vehicle crash load was correct. The thesis researched the fault of the structure on the crash safety according to FEA results. Frame is an important part of a minibus. We analyzed the mechanics performance and the design method about the energy absorbing ability and abnormal deformation of the frame. Then a series of improvements of vehicle structure, including frame, front wall, side wall, were made.Finally, the vehicle's absorbing ability and the strength were better after comparing the optimal design and the old design .The improvement methods above were suitable for the design and research of similar vehicle. At the same time it can he1p reducing the experiments of product and the cycle time of design, so it had very important significance in the optimization of crashworthiness on the vehicle.