Optimum Design Of Front Cabin Structure Of Electric Vehicle Based On Frontal Crash Safety

Facing the shortage of global petroleum energy and the serious pollution of automobile exhaust,the electric vehicle has become an important direction of today's automobile development because of its clean and renewable energy advantages.Moreover,due to the characteristics of high cost and long cycle of electric vehicle development,most of the automobile companies are refitting or reconstructing on the basis of the original traditional cars,which will bring great damage to the original structure and bring hidden trouble to vehicle safety.Therefore,the design of collision safety for electric vehicles is an important and meaningful topic.In view of the above problems,this paper takes a pure electric vehicle as the research object of the front structure crashworthiness optimization.The finite element simulation models of the 100% front collision and 40% bias collision are established,and the accuracy of model were validated.Then the crashworthiness indices such as front crushing deformation,energy absorption of vehicle parts,acceleration of vehicle body and intrusion of the cowl panel structures were analyzed based on simulation results.Against with the poor performance of the vehicle frontal collision,crashworthiness topology optimization method is applied to the vehicle 's development process,and combined with the crushing theory of the thin-walled tube,and material distribution from topology optimization results and practical enginee ring factors,to guide the initial design of the front rail.Then the front rail structure as the foundation,followed by engineering interpretation of other parts in front cabin.Finally,the re establishment of the vehicle 100% positive impact and 40% offs et impact finite element model,verify the effectiveness of collision resistant cabin structure topology optimization.The results showed that: in the 100% frontal collision of the vehicle,the effective energy-absorbing space in the front cabin is more fully utilized.The energy absorption of the front longitudinal beam is increased from 13285 J to 16867.1J,which is increased by 30.0%.The energy absorption effect of the front longitudinal beam has been greatly improved.Vehicle collision acceleration peak value decreases,and acceleration peak time postpones backward.The whole collision continues process increases,which greatly improves vehicle crashworthiness.In the process of 40% offset collision of the whole vehicle,the crush deformation of the front cabin has been greatly improved.The deformation of the bumper beam has been significantly reduced,meanwhile the crush defomation of the front longitudinal beam has been increased.The maximum deformation of the dash panel was reduced from 336 mm to 291 mm,a reduction of 45 mm,which reduced the amount of intrusion into the occupant cabin and reduced the threat to the occupant's life safety.