Research On Crashworthiness Optimization Design Of Frontal Crash Structure Of A Passenger Car

The frontal crash safety performance of the car has always been a complex and important problem,the crashworthiness of the vehicle's frontal impact structure is directly related to driving personal safety in the event of a traffic accident.In recent years,with the vigorous development of new energy electric vehicles,electric vehicle crash safety research is also a very urgent task.In this paper,based on an electric vehicle,the crashworthiness about frontal crash of this vehicle is optimized.Firstly,the finite element model of a pure electric vehicle is established,and a lot of research on the key components of the vehicle's frontal crash is referenced.The thickness of eight key components,including the front bumper,the energy absorbing box,the front longitudinal beam,the fender,the engine cover,and so on,are chosen as the design variables.The total energy absorbed in the course of vehicle collision,the peak acceleration value of the vehicle and the mass of the eight components are selected as the optimal response.The goal is to maximize the energy absorption of the vehicle,minimize the vehicle's peak acceleration and the total mass of the optimized component.Secondly,the optimal Latin hypercube method is used to collect 50 sets of sample points and the response surface approximation model is established.An improved non dominated sorting genetic algorithm is used to solve the multi-objective optimization problem and then a deterministic optimization scheme is obtained.Considering the influence of noise factors,the reliability of the certainty optimization scheme is evaluated by the 6 ? reliability optimization method to get the uncertainty scheme.The results of uncertainty optimization meet the design requirements,and the purpose of improving the vehicle's frontal crash safety and lightweight design is achieved.The results show that uncertainty programs are more reliable and achievable.And lastly on the basis of the stringer's structural parameters of this vehicle,the aspect ratio of the stringer's cross section and this stringer's thickness values are taken as optimization design variables.The stringer's energy absorption during frontal collision and the total mass are taken as the optimization design target.The response surface model and the improved non dominated sorting genetic algorithm are used to get the optimal solution,and then the overall energy absorption of the stringer during frontal collision is improved,the total mass of the stringer is reduced,and the deformation result of the stringer is better.