| Side impact of the vehicle is one of the key means for proving passive safetyand safety after crash, which are very important target for reflecting the safety ofthe vehicle. The passive safety research is mainly on decreasing the occupant injuryin the crash, include body structure, roof and door strength, damping performanceof both body in white and interior trim.In china, the regulation for side impact has not compulsively executed until now.This kind of test and simulation is rare. The amount of side impact accident is morethan 30% of overall transportation accident. Both the space and the rigidity of theside structure are weak than that of the front structure. The energy absorbing abilityis weak too. Both the occupant physical injury and physiological injury are veryserious. Different from the frontal crash, side crash consists of special analysismethod and kinetic and mechanical characteristics. The harm is very serious and itis an important aspect to estimate the crashworthiness. The deep research on sidecrash is imperative under the situation.Main parts' mathematic model of CA7220 are built, treated and simplifiedaccording to the characteristics of FEM and simulation. All the conjunctive place ofwhole body is roundly inspected and corrected. The welding, connecting andcontacting technological situations of rear car are simulated by analysis software.The geometrical, material and mechanical model of Moving DeformableBarrier(MDB) is built by EEVC standard.Based on a typical structure for side impact, mesh plotting, material definition,weld technology and contact situation are clearly analyzed and compared, andabundant experience is accumulated inside. It can guarantee enough calculatetolerance and increase the calculate efficiency at the same time. Adding concentratemass at the proper place can remedy the effect of the overall mass lacking causedby simplification and deficiency and make the crash model similar to the real car aspossible. According to the ECE R95 regulation, side impact simulation for car bodyassembly has been done. The analysis consists acceleration variety, force variety,energy variety, time step variety and so on. The procedure and the result of thesimulation are available comparing with the rear impact test data and it can be usedas credible evidence to prove the rear car test. A relative optimal scheme isadvanced oriented to the result occurred in both of test and simulation and itregarded the production situation, technology condition, modification difficulty andimplementation difficulty. Some stiffener panel is added and the rigidity of bothend of B pillar is optimized. After simulating for modified structure, the resultshows this structure has a good characteristic of energy absorbing and animprovement of the acceleration curve and the energy curve. The modified schemecan raise the car side impact crashworthiness and it is available.In this thesis, a method applying to impact simulation combined severalsoftware is introduced by studying, using, comparing the characteristics amongseveral CAD and CAE software. The software includes CATIA V5,Hyper Mesh,Pam Crash and so on. This method is useful and convenient to data making andtransferring. The research about the simulation for side impact crashworthiness ofCA7220 is completed by using CAE analysis method. The result is compared withthe practice car test. A modified scheme and an efficient working procedure arecarried out. Being the analysis and modification of automobile sidecrashworthiness can improve the automobile passive safety research at home. Thisresearch can be a method to validate both the test and the simulation each other andcan provide abundant theoretical proof for product promotion, shorten the passivesafety test period, decrease the risk and the cost in promotion stage, and upgradethe product performance. The method and the data provided in this thesis are usedthe experience of other model for reference.x...
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