Research On Analysis And Optimization Of The Electric Bus Body Structure

With the sustainable development of energy,environment and the automobile industry in China,the contradiction of sustainable development is increasingly prominent,pure electric bus has become the main direction of the development of urban public transport.However,in the process of the development of electric vehicles,facing the contradiction of the power battery energy is generally relatively low and users want to get a long range of driving mileage.In order to solve this contradiction,the realization of light weight of electric bus body is one of the most effective solutions.Using the software platform of HyperWorks,finite-element model building,static analysis and modal analysis of the electric bus have been conducted.Through the static analysis separately under bending,emergency braking,emergency turning and torsion condition,the body strength and stiffness qualifications have been tested.With the results of modal analysis,the natural frequencies and vibration modes of free modal have been calculated,besides,the body structure dynamic characteristics can be predicted.Based on the research of the finite element modeling method,this paper completes the static analysis finite element model of the electric bus with high engineering application value.On the established electric bus body finite element model were body modal analysis,the results of the simulation calculation,the dynamic performance of electric bus body structure prediction,for the follow-up based on the finite element model of the body strength analysis and lightweight optimization design to provide the basic design.Complete electric bus body bending condition,emergency braking,sharp turning conditions and torsion under the condition of loading and boundary conditions are created,finite element analysis,complete body static stiffness test,judge the strength of the electric bus body stiffness is in the allowable range.In this paper,the lightweight design of the electric bus body structure is completed.Through hydrodynamic static stiffness properties of the structural parameters of the sensitivity analysis of influence on body,to identify the body stiffness influence of key components,on the basis of the optimization design,set the corresponding design variables,response,objective function and design constraints,based on multiple constraints of lightweight body design,to reduce body mass and improve the dynamic performance of body structure.Its body mass as the objective function,under the conditions of each should force and modal natural frequency as the constraint condition,body frame main bar thickness as the design variables,the electric bus body were lightweight analysis,to meet the intensity of the whole,the low order natural frequencies of the stiffness and body,reduce the body mass.