Crashworthiness Design Of Thin-walled Structure Based On Topology Optimization

Vehicle crashworthiness design is one of the most difficult problems being addressed in design optimization.On the one hand,topology optimization method could greatly improve the structural crashworthiness in certain quality.However,traditional topology optimization methods to solve large deformation nonlinear optimization problems encountered great difficulties.On the other hand,Thin-walled structures have been widely used as energy absorbers in automobile and aviation,due to their good performance on energy absorption.However,Traditional design methods of thin-walled structures are not enough to fully release the potential of its energy absorption.Herein,the research presents a topology optimization method to guiding the crashworthiness design of typical thin-walled structures.Considering the nonlinear optimization problem in the crash process,this paper proposes an element-energy-based topology optimization method,which based on two assumptions between elemental quality and energy.The first,there is a linear relationship between the energy absorption and the quality when the quality varies small enough.Secondlly,where more energy is absorbed should be allocated more quality.This method does not need sensitivity analysis by gradient derivation.In order to verify the feasibility of the method,the paper carries out crashworthiness design of TRB structures.The top-hat beam similar to B column in automobile is studied.Firstly,the accuracy of the FE model is validated by experiment data.Then uses the method proposed in this paper to design the automobile B column with TRB structure.In order to further illustrate the practicability of the TRB design method,the optimal design of automobile bum per is carried out.The results show that with the same mass,the energy absorption performance of the optimized B column and automobile bumper is improved greatly.Combining the proposed method with the design of multi-cell structures to optimize the cross section of the rectangular multicell tube.The influence of different strategies on the optimization results are studied.Besides,it carries out crashworthiness design under different working conditions.The results get the obvious topology configuration and the energy absorption performance of the optimized rectangular multicell tube is improved obviously.In the final,the correctness of the method and the feasibility of guiding the crashworthiness design of multi cell structure are illustrated again through comparative analysis the results obtained by the presented method and HCA.