Finite Element Analysis And Structureoptimization Of Side Impact For A Passenger Car

Traffic accidents can make people suffer from serious injuries and large economic lost,the vehicle side impact collision, as one of the most common types in fatal crashes,includes car-to-car side impact and car-to-object collision, which also includes the car–to-narrow pole object that can cause the more serious injury, so it is necessary to study thetwo side impact patterns.The crew is the main structure to withstand the impact force inside collision, so its parts play an important role in bearing and scattering the side impactforce. The ideal passing path of inpact force can effectively reduced the injury risk ofoccupants in side impact through leading and absorbing the impact energy to reduce theenergy which finally passed to the occupants.This paper assesd the crashworthiness and the protection for occupants of a domesticcar through the MDB(moving deformable barrier) side impact and the pole side impact.Bycomparing the impact response of the two side impact patterns,based on the method ofimproving the force passing path to increase the energy absorption, structure optimizationwas conducted through the material and structure match of side components. Theoptimazed model had better crashworthiness. The specific work were as follows:1. According to requirements of crash simulation analysis, the CAD model of adomestic passenger car was geometryly cleaned and divided into elements by using thesoftware of Hypermesh and ANSA, then through endowing the real mechanical behaviorof materials and properties to the parts and setting up joints to make assembly, a CAEmodel of the car was finally established.2. The MDB side impact simulation model according to the requirements of thenational side impact regulation and the pole side impact simulation model according toEuro-NCAP were established, while the input and output parameters were set up, as wellas the section force of some main parts which can bear and pass the impact force and theinterface types that affect the response of impact. Finally, in order to ensure the accuracy ofthe simulation, some necessary adjustments was made to the model compared to the realcar.3. The side impact of this car were simulated in this paper and the simulation results ofMDB side impact and pole side impact were analyzed. This paper mainly compared andanalysised deform response of the crew, the bearing force capacity and energy absorptioncharacteristics of the main bearing force and energy absorption components and the response of B-pillar, preparing for structural optimization.4. Through output the section force of main parts, the passing paths of impact forcewere find, and the structure of the main parts which formed the crew were analyzed, thenthe optimazition were conducted according to the key parts which affected the energyabsorption in the impact. Based on the structure-improved model, an orthogonal test wasconducted with the help of the comprehensive equilibrium methods in order to analysis theeffect of the strength of the crew parts on the performance of impact. The results showedthat the performance of this car in the side impact was improved after optimization.