Crashworthiness Analysis And Optimal Design Of Frontal Structure Of An Electric Vehicle

In order to comply with the demand of "energy conservation, green low-carbon ", vigorously develop the industry of electric vehicles has become the main way for the sustainable development of China’s automobile industry.Compared to conventional vehicles, electric vehicles have more stringent security requirements in crash safety.Automotive crash safety is one of the key elements of car design, and how to improve the crashworthiness in a collision is an core issue in the design of car safety.With the means of theoretical analysis, mechanical modeling, numerical simulation and experimental verification,frontal crashworthiness structure of one electric vehicle was analyzed.The front rails were optimal designed and two kinds of new contraction beams were designed.Crashworthiness safety of the vehicle body was improved after optimization.The main work done and the main results obtained are as follows.1. Aiming at the basic algorithm of LS-DYNA,collision theory of finite element and the way of collision simulation were deeply investigated.According to the RCAR and C-NCAP, low-speed (16km/h) frontal crash structure and high-speed (50km/h) frontal crash structure collision model were built by Hypermesh and LS-DYNA software to simulate front impact barrier test of the electric vehicle.2. Based on collision simulation results credible analysis and the experimental collision data of original conventional car,frontal crashworthiness structure was analyzed at low-speed collision and high-speed collision.The results show:the bending performance of the backend of front rails is not good and crashworthiness effect of energy-absorbing beam should be improved.3. Aiming at the problem of bending performance of the backend of front rails is not good and instability of front rails,the location of the internal reinforcing plates of front rails were changed.The control deformation of front rails were optimal designed.In order to verify the optimization results,the crashworthiness of the frontal structure models were compared before and after optimization.4. Based on the principle of tube free flip,two kinds of new retractable beams were designed.Take low-speed collision and high-speed collision for examples,the crashworthiness of original energy-absorbing beam and new energy-absorbing beams were contrast analyzed by the crash behavior of the collision.The results demonstrate that the energy absorption of the new retractable beam increased by18.0%and the mass reduced23.6%.The new retractable beam shows good crashworthiness effect.