Finite Element Analysis And Improved Design Of MPV Frontal Collision Safety

China's traffic accident casualty rate in the last few years has been at a high level,to the country and the people brought huge economic losses.It is of great social and economic significance to the passive safety research of automobiles.In the car design stage,the collision safety performance of the vehicle must be simulated and optimized to improve the safety of the collision.This will not only reduce the number of real test,but also reduce design costs,speed up the development of new cars.In this paper,the finite element basic theory,time step andthe nonlinearity of the simulation process and some other parameters are described in detail,which provides the theoretical basis for establishing the finite element model of frontal collision.In order to complete the simulation analysis of the rigid impact of a certain MPV model,a vehicle collision grid model composed of shell element and three-dimensional solid element is established.The corresponding material properties are set for the whole vehicle parts,and the connection between the parts Also selected the corresponding connection;created a rigid wall and different contact methods;through the above operation to establish a vehicle front collision finite element model.According to GB 11551-2014 on the creation of a good model of the 51 km / h positive rigid collision simulation calculation.The simulation results are analyzed from the aspects of speed,acceleration,deformation and energy of body structure.And did not meet the design requirements of the structure was improved design.For the purpose of reducing the peak acceleration,the front beam and the front pillar reinforcement plate are carried out.Strengthen the design,the longitudinal beam assembly has been optimized.The simulated model is simulated again,and then the results are compared with the original model.The results show that the peak value of the model is optimized effectively and the other aspects meet the design requirements.The safety of the vehicle is improved.The results of this paper provide theoretical guidance for the later optimization design of the model.