Study On Crashworthiness Of The Frontal Longitudinal Beam On Front Crash

The energy absorption of the frontal longitudinal beam is mainly decided by itsstructure, material and automobile structure and etc, and it directly affects the safetyability of the front crash of passenger car. The paper puts a designing vehicle asobject of study in the project which is called "China’s high level car independentinnovation capacity building"(that is zhongqi project). It discovers the frontallongitudinal beam of the car has problems in design by means of combining crashsimulation test and real vehicle collision test, and applies genetic algorithm to dooptimizing design for the inducing groove structural parameters of the frontallongitudinal beam in order to improving the energy absorption and the stability.Firstly the paper conducts crash simulation tests to the frontal longitudinal beamof the designing car, and it adopts real vehicle collision tests to proving the simulationresults, and proves the frontal longitudinal beam exist shortcomings in the stability incrash simulation tests. As it has shortcomings in the stability, it affects the foldingsequence and energy absorption of the frontal longitudinal beam, and influences thevehicle safety ability.Secondly, According to the pole’s stability theory in Mechanics of materials itresearches stability ability, and finds relationship between the variables, and it as oneof the optimizational function. According to the deformation mode of the frontallongitudinal beam the energy absorption ability is divided into two parts for studying,one part is caused by elastic deformation, another is caused by plastic deformation,and it analyses the energy absorption of the frontal longitudinal beam in Elastic andplastic mechanics theory Due to the two parts deformation is relatively complex in thefront crash of passenger car, the paper adopted the response surface method to fit theits function relation, and as anther optimizational function.Finally, according to creating optimizing function of the energy absorption andthe stability it applies genetic algorithm to do optimizing design for the structuralparameters, effectively improves the and the stability.After optimization, frontallongitudinal beam doesn’t produce irregular bend, and The energy absorptionimproves5.1KJ,its optimization effect is better.By means of combining simulation analysis and real vehicle collision test, itsynthetically applies Elastic and plastic mechanics, mechanics of materials and etcrelated theory to research the stability and energy absorption of the frontal longitudinal beam, and based on it applies genetic algorithm to do optimizing designfor the its structural parameters to make that its stability and energy absorption has alarger improvement, optimized structural parameters is instructive. Moreover, thepaper’s research process and method has universality, it also applies to the othersimilar engineering problems in structure analysis and optimization, and providestheory reference for the problems, it has a good engineering guiding significance.