FEM Analysis And Weight Lighting Of The Pure Electric Bus Body

In recent years,energy saving,environmental protection and safety has been the main problems faced by automotive industries in sustainable development.Automotive lightweight design is one of the principal ways to achieve energy conservation and emissions reduction.As the main bearing weight parts of bus,body skeleton accounts for about 30% ~ 40% of the bus total weight.Weight lightening for bus body frame plays an important part for reducing the entire bus quality.This paper carried out the finite element analysis of the bus body frame.The lightweight of the bus body frame was investigated based on the topology optimization techniques.First of all,the Finite Element Model of bus body skeleton was built,the Finite Element Analysis of the model was performed.Considering bending condition,torsion condition,emergent turning condition and emergent braking condition,statics analysis were carried out under these four typical operation situation,stress value and the deformation of the structure was calculated.Then modal analysis for the coach-body frame,through which the free frequency and vibration mode characteristics of first ten steps of the structure were gained,the results are correctly and provide the basis for lightweight design of the bus skeleton.Secondly,Opti Struct was employed for the lightweight design of the bus body.Topology optimization design for the bus body skeleton was performed in a variety of solutions.Comparing the results of the analysis,the quality of the best distribution for the bus body structure was obtained.Based on the optimization result,the design principles and the manufacturing technique principles of body skeleton,the bus body skeleton structure was extracted.Finally,statics and modal analysis for the new bus body frame were carried out.Compared with the original bus body frame,the results show that performance of the new body frame is increased,the quality is cut down by about 6.96 percent,to acquire a better result of weight lightening.The research of this paper made some contribution to rich the analysis results and related data of the optimization design for the bus body structure.