某MPV车型顶部结构抗压性能研究与B柱优化

Study on Compressive Performance of Roof Structure and Optimization on B-pillar of MPV Vehicle

针对汽车翻滚事故中,车顶抗压强度不足的问题,建立某MPV整车有限元模型,根据FMVSS216a法规及其试验方法,对其顶部抗压强度进行模拟仿真分析。通过顶压工况下仿真与试验结果对标分析验证了有限元模型的准确性。根据仿真与试验变形及截面力分析等得出B柱与顶盖横梁是主要承载部件。选取B柱内板及顶盖横梁的材料与厚度为设计变量,通过拉丁超立方抽样设计样本空间,构建Kriging近似模型,采用粒子群优化方法进行多目标优化设计,并对优化方案进行验证。仿真结果表明:刚性墙达到3倍质量力时的位移为64.30 mm,下降15.04%,B柱及顶盖横梁1、2的比吸能增加21.82 J/kg,提高20.2%,B柱的优化效果显著。

According to the standards and regulations of FMVSS 216 a,the compressive strength of the roof has been investigated and analysed using finite element method. The feasibility and reliability of the simulation are validated by experimental results. The simulation results,in terms of the deformation and force analysis,demonstrate that the B-pillar and roof beams are the critical components when pressure is applied on the vehicle,e. g. when rolling in traffic accident. The material and thickness of the B-pillar and roof beams are selected as design variables. The sample space is designed by the Optimal Latin Hypercube sampling. The Kriging approximation model was constructed. Based on Particle Swarm Optimization method,the multi-objective optimization is carried out and thereby being verified. The simulation results elaborate that the displacement decreases 15. 04%( at approx. 64. 30 mm) when the force applied on the vehicle is three times larger than the mass of the equipment. The energy absorption of the B-pillar and roof beams is increased by 21. 82 J/kg( up to 20. 3%).