Finint Element Analysis And Linghtweight Research Of Metro Battery Box

As one of the essential components on subway vehicles,the subway battery can provide emergency energy for the vehicle when the train encounters special circumstances.As the structure for loading the battery,the battery box has the important role of bearing,packing and retaining the battery,and the reliability of its structure influence affects the working properties of the battery under special circumstances.The traditional box structure has disadvantages such as poor reliability,low material utilization and excessive weight,which affect the working performance of the train.Therefore,this paper takes the battery box of a city subway as the research object,analyzes the static and dynamic performance of the box structure,and carries out research on lightweight design.The research process has theoretical significance and industrial application value for reducing manufacturing costs and improving driving safety.The main contents are as follows:Firstly,the finite element model including covering,main frame,and battery trolley structure is established based on the 3D geometric model of the battery box and material parameters.According to the relevant test standards,the load conditions when the train is in operation are established,and the static analysis of the box structure under different working conditions is carried out.The calculation results show that the static strength of the box meets the requirements,but the utilization of the material is low.Secondly,aiming at the different structural parts of the battery box,a method combining topology optimization,size optimization and material lightweight is proposed to study the lightweight of the box.Among them,the topological optimization method based on the variable density method is applied to find out the optimal material arrangement of the box lugs;the thickness of the main frame structure is designed for dimensional optimization;and the aluminum alloy lightweight material is used to replace the stainless steel material of the battery trolley structure.Finally,the lightweight box structure is re-modeled and calibrated with static strength analysis and modal analysis.Based on the standard requirements for shock and vibration testing of railroad equipment,the fatigue life of the box structure under random vibration load is estimated in the frequency domain based on Miner’s linear fatigue cumulative damage theory,and the box is simulated and analyzed based on half-sine pulse waveform for impact testing.