Crashworthiness Analysis And Optimization Design Of Imitated Horns Thin-walled Energy-absorbing Tube

The thin-walled structure is widely used in the energy absorption and dissipation system of various vehicles because of its good energy absorption effect.The design of the thin-walled structure with good and excellent performance is of great significance to the guarantee of lightweight and safety of vehicles.In recent years,many scholars have tried to integrate bionic elements into the development of thin-walled metal structures.In order to further improve the crashworthiness and energy absorption of thin-walled structure.In this paper,based on the biological structure characteristics of ox horn,the similarity between it and the thin-walled structure was analyzed,and three structural characteristic parameters of ox horn were extracted,namely,Horny shell,Restrained beam and Core,and a imitated horns thin-walled energy-absorbing tube was designed.In order to explore the deformation mode and crashworthiness of the bionic tube,and to optimize the size of the two kinds of bionic tube with better crashworthiness,this paper mainly carried out the following work:(1)Based on the theory of finite element analysis,the finite element model of the circular tube is eatablished,and the collapse deformation mode and the number of folds of the circular tube are analyzed.The simulation results were compared with the experimental results,and the validity of th e finite element model of the circular tube was verified.The results show that the finite element model of the circular tube can be applied to the construction of bionic tube.(2)Take Horny shell,Restrained beam and Core as factors to design the full factorial experiment.Then,finite element software was used to analyze the energy absorption and deformation mode of the bionic thin-walled structure,to discuss the impact of three factors on the crashworthiness of the bionic tube,and to determine the better crashworthiness of the thin-walled structure.The result show that:The three factors all have a certain influence on the crashworthiness of the bionic tube.Finally,two kinds of bionic tubes with better crashworthiness were selected,and it was found that the two kinds of bionic tubes has better crashworthiness and energy absorption than the traditional thin-walled energy absorption tubes.(3)In order to find the optimal crashworthiness size of bionic tube and further improve its crashworthiness,two kinds of bionic tubes were selected for size optimization design.Taking the wall thickness and length as factors,a full factorial experiment is designed to investigate the influence of size on the crashworthiness of the bionic tube.The results show that both the wall thickness and length have certain influence on the crashworthiness of the bionic tube.According to the selected sample point data and simulation value,this paper determine the quadratic response surface fitting functions of specific energy absorptio n,peak crushing force and crushing force efficiency in the end.Then according to these kinds of functions,the fitting function of weighted value is eatablished.Finally,we obtain the wall thickness and length which made the weighted value reach the maximum value to complete the optimization.