Frontal Impact Analysis And Structure Optimization Design Of A Certain Electric Vehicle

With the rapid development of the economy and the continuous improvement of people's living standards,the demand for automobiles is becoming more and more vigorous by the general public.Due to the fact that the traditional fuel automobiles will cause a great deal of pollution during the use process,today's society,the concept of "energy saving,emission reduction,green and low carbon" has been deeply rooted in the hearts of the people.Therefore,the country is now vigorously promoting and developing new energy vehicles,and electric vehicles are the leading sheep.However,compared with traditional fuel vehicles,electric vehicles have a large difference in power composition,the safety problems of electric vehicle collision has its particularity,based on this,in order to ensure the safety of people's life and property,to explore how to effectively improve the safety performance of electric vehicle in the collision process becomes the focus for researchers.In this study,a type of electric vehicle which is being developed in an enterprise is investigated as the research object,by means of theoretical analysis,finite element modeling,numerical simulation calculation,the frontal crash safety performance of the pure electric vehicle has been systematically studied.Later,the light weight optimization design for the key components of the electric vehicle has been investigated.In this paper,a finite element model of a certain electric vehicle is established and the frontal impact numerical simulation is carried out.After that,the credibility of the simulation results is analyzed and the accuracy of the model is determined.Then,the key data and the deformation of vehicle and key components related to the frontal crash performance are analyzed in detail,so as to evaluate the frontal crash safety performance of the electric vehicle.Finally,the design of light weight optimization for the three key components of the frontal crash process,namely the front collision avoidance beam,the front energy absorbing box and the front longitudinal beam is carried out.In the optimization process,the thickness of the front collision avoidance beam,the front energy absorbing box and the front longitudinal beam is a continuous design variable,the total mass M is set as the object function.Because the acceleration value at the lower end of the B pillar and the invasion of the front coil are important indexes to evaluate the safety of collision,therefore,the peak acceleration at the bottom of the B pillar as well as the maximum amount of the invasion of the front coil are chosen as the constraint condition.After that,metamodeling with the radial basis function(RBF)together with the genetic algorithm(GA)are used to optimize the design.In order to save the time of simulation calculation,the finite element model is properly simplified and the validity of the model is verified.Comparing to the original condition before optimization,the simulation calculation results show that the weight of the whole components which contain the front collision avoidance beam,the front energy absorbing box and the front longitudinal beam has reduced 4.22%,the peak acceleration at the bottom of the B pillar has reduced 1.80% and the maximum amount of the invasion of the front coil has reduced 4.76%.To some extent,the frontal crash safety performance has been improved.Meanwhile,the light weight of the structure has achieved good results.