The Finite Element Analysis And Optimization Of Vehicle Torsion Bar Spring Based On Hyperworks

Elastic element, which was an important part of the suspension system, had a keyeffect on ride performance. By taking a typical torsion bar spring in a certain car as theresearch object, this paper calculated the role of the torque on the torsion bar spring basedon different operating conditions encountered in the analysis of the vehicle. Stressdistribution and deformation were got by FEA software. Based on these results,optimization design was carried out on the physical dimension of torsion bar spring.Force analysis was carried out in larger impact on car typical operating conditions andthe formula of the four kinds of typical operating conditions of the tire ground point loadwere determined respectively, by analyzing a variety of conditions encountered in theprocess of moving. The ground point force calculation was accomplished with knownrelevant parameters.Load of lower control arm ball joints in front suspension was measured aftersimulation as taking the load of the ground point as the known parameters in the certainautomotive suspension model that had been established in ADAMS/Car, on top of which,the torque of the torsion bar spring was calculated according to the length of the torsionbeam.The model of torsion bar spring virtual prototype, established by using Pro/E, wasintroduced HyperMesh and statical analysis was carried out and the stress diagram as wellas strain diagram was obtained. The maximum stress and strain increased along with the riseof torque moment on torsion bar spring in all4working conditions. Optimization on thephysical dimension of torsion bar spring can be carried out after above-mentioned steps.Load steps of were created in HyperMesh and then order normal modal analysis of thetorsion bar spring were accomplished. The result demonstrates that torsion bar spring wouldnot resonate when automobile traveling under random road conditions. As a result, factor ofnatural frequency for the automobile can be ignored in the optimization process.Established torsion bar spring optimization mathematic model with torsion bar springdeformation energy as objective function, with diameter and effective length of torsion barspring as optimization goal, optimization of the deformation energy of torsion bar springwas finished by using an optimization toolbox of MATLAB, as a result of which, the optimal diameter was29mm, and optimal length was1200mm, and deformation energy oftorsion bar spring after optimization was10.8%higher than that without being optimized.With diameter of inside and outside of torsion bar spring as optimization goal when usingannular section, the optimal diameter was29mm, and optimal length was1200mm, anddeformation energy of torsion bar spring after optimization was6.8%higher than thatwithout being optimized. After the optimization, the torsion bar spring meets therequirement of operating and lightweight which improved ride comfort.In this paper, method of traditional mechanical calculation, technology of mechanicalsystem simulation and finite element method were combined and applied to designing aswell as analyzing process, which promoted the combination property of torsion bar springand guaranteed the stationarity of the automobile. The research work of this paper was ofimportant realistic meaning.