Research On Topology Optimization Design Of Small Electric Vehicle Frame Under Multiple Operating Conditions

As society pays more and more attention to environmental protection and energy saving,pure electric vehicles are now becoming a hot spot for research and development in various countries around the world.The advantages of low pollutant emissions,low noise and high energy efficiency are unmatched by traditional fuel vehicles.As one of the important components of the car,the frame bears the mass load of the cab,powertrain and all other parts,and it also bears the vibration,impact and distortion from the road surface under different working conditions.If it can meet the various performance requirements of the frame,at the same time increase the material utilization rate and realize the lightweight of the frame,it will be of great engineering use value.Especially at the current stage where the development of battery technology is still restricting the development of electric vehicles,reducing the vehicle’s own weight to improve endurance means that the cost of the entire vehicle can be greatly reduced,which is conducive to the promotion of electric vehicles.Therefore,the topology optimization design technique should be used in the early stage of the frame structure design to obtain the frame topology in the design domain.The main research contents of this article are as follows:(1)Create a simple model of a small electric vehicle frame based on the traditional car frame,and propose two small electric vehicle power battery layout schemes;carry out the frame of the two schemes under four typical working conditions of bending,torsion,braking and turning Finite element analysis,and finally choose the layout of the small electric vehicle frame in the middle of the power battery pack;(2)Construct a topological optimization mathematical model with the smallest volume as the target and the overall structural flexibility as the constraint;propose a solution method for the multi-case weight ratio assignment problem;establish a local topology optimization finite element model of the small electric vehicle frame in Hypermesh;weight Substituting a weighted flexibility function with weighted flexibility as the constraint and the minimum volume of the structure as the goal,the multi-mode topology optimization of the small electric vehicle frame is completed in Hypermesh;a three-dimensional model of the small electric vehicle frame based on the topology optimization results is constructed.Compare the results of static analysis and modal analysis before and after optimizationThe optimization results show that the partially optimized frame structure meets the requirements of use,reducing the overall mass of the frame optimization area,and improving the effective utilization of materials,which is of great significance for further structural optimization research.