Finite Element Analysis Of Car Front Bumper Collision

The statistics from around the world show that the number of deaths is constantly increasing every year, because of road traffic accidents, so car accidents become one of the major social problems that endanger the safety of human life. At the same time automobile collision’s safety issues is getting more and more attention around the world. And in the process of vehicle collisions, the highest probability of occurrence is the front, the first relates to the front bumper of the collision.In the case of car crash, bumpers have their indispensable "roles in impact energy absorption, car body protection, passenger and pedestrian injury alleviation and prevention. Therefore improving bumper crashworthiness and energy absorption characteristics is very realistic and important for improving vehicle crash safety.On the base of systematic summarization on the critical problems, research methodologies and research situation of bumper low speed impact, according to CFVSS215bumper low-speed collision regulations, firstly, some car model is established in this paper using CATIA software. The geometric model of meshing, the definition of material properties as well as component connection is done by using Hypermesh software. And choosing LS-DYNA software, boundary conditions and the control conditions are set for the vehicle collision model.In order to more accurately study the bumper system crashworthiness in low-speed collision, the high-speed (50km/h) crash simulation is firstly done for the finite element model of the vehicle, and analyzing vehicle deformation, displacement, velocity, acceleration and energy from the simulation results obtain the accuracy of the finite element model. And on this basis, according to CFVSS215bumper low-speed collision regulations, processing simulation study of the8km/h collision and the4.8km/h angle collision on the bumper system determine the evaluation method of the bumper and establish the failure criteria of the bumper. Via analysis of deformation, velocity and acceleration of the bumper proposes advice on crashworthiness of the bumper beams.Then based on the analysis of simulation, according to the actual study, a new structure of the bumper is established on the original body model, and process simulation study of the8km/h collision on the new bumper system. Using of the simulation results analyze rationality of the new bumper from the aspects of deformation and equivalent stress-equivalent plastic strain. And then, comparing the new bumper with the original on energy analysis we obtain better crashworthiness of the new bumper structure. So that shows the reliability of the new bumper.