Simulation Analysis And Energy-absorbing Parts Design Of Vehicle Frontal Collision In Low-speed

Nowdays,most of the automobile crash safety tests are on the research of high-speed collision,but with the rapid development of China's automobile industry and increase in car ownership,low-speed collision occurs more and more,especially in traffic developed cities.The study of low-speed collision not only improves the service life of automobile,the cost performance of automobile and the safety performance of automobile,but also reduces the cost of vehicle maintenance,and save the cost of vehicle life cycle.In this paper,a finite element model of a vehicle is selected as a prototype to validate the validity of the model;According to the IIHS low-speed frontal collision law,a low-speed complete frontal crash simulation model is established.By observing and analyzing the plastic strain which are some components and reading the IIHS low-speed collision,the effective plastic strains of condenser,radiator and front sill is selected as the standard of judgment.By analyzing the simulation results,it is judged that the original model does not accord with the standards of IIHS low-speed collision regulation;After analysing the energy absorption of the bumper parts,this paper designs the crash box which is between ribs of the bumper and the front sill to increase the energy absorption of the bumper system according to the size of the actual vehicle;The topology optimization design of the crash box is based on SIMP variable density,and the thickness of the bumper reinforcement is appropriately optimized;Finally,to verify the scientific and effectiveness of the redesigned bumper energy absorption system,the optimized model is simulated according to the IIHS low speed collision code.According to the results of this study,by increasing the thickness of the bumper ribs,the bumper energy absorption efficiency is increased by 18.1%;By increasing of the crash box,the energy absorption efficiency of the bumper system is increased by 16.85%;After optimizing of the bumper system,the effective plastic strains of the condenser and radiator is reduced by 22.5%,which is reduced by 41%in the front sill,and the relevant data is in accordance with IIHS low speed collision regulations.According to the results of this study,it can be concluded that the increase of crash box can effectively improve the energy absorption effect of bumper system,optimizing the bumper system contribute to reduce the damage of some important parts in cars and the maintrnance cost of the collision.This paper provides some theoretical basis and technical support for the study of complete performance of low speed collision in China.