Accurate Modeling And Experimental Study On Energy Absorption Characteristics Of Thin-walled Composite Structure

Composite materials are widely used in aerospace,automotive,electronic and electrical fields because of their many advantages,such as light weight,high specific strength,high specific modulus and strong design ability.In automobiles,composite materials usually are used as covering parts and structural parts,when it comes to energy absorbing structures,composite structures gradually show the advantages of traditional metal structures.The energy absorption characteristics of axial crushing of composite thin-walled circular tubes are closely related to the type of material,the size of the structure and the laying method of the fiber,In this paper,the energy absorption characteristics of carbon fiber reinforced composite thin-walled circular tubes of axial quasi-static compression are studied based on experiment and numerical simulation method,the influence of different parameters on the energy absorption was analyzed,and then optimize the parameters through an agent model.Firstly,in the experiment of axial quasi-static crushing of carbon fiber reinforced composite thin-walled circular tubes,the effects of different crushing stroke on the energy absorption characteristics were studied under the same parameters,draw the conclusion that the energy absorption characteristics was not affected by crushing stroke.Three kinds of length of which has three layer number of specimens were tested to analysis the the influence of length and number of layers on the energy absorption characteristics.It was found that,reasonable ratio of length to diameter can make full use of the energy absorbing properties of composite thin-walled circular tubes.Secondly,two modeling methods were established to simulate the axial quasi-static crushing based on Hashin failure criterion,verified the feasibility of the numerical simulation method.It was proved that two layer shell element modeling is more advantageous.The model with trigger mechanism was built to explore the difference between the composite thin-walled circular tubes with and without trigger,then the results of energy absorption of impact and quasi-static conditions are compared.Finally,the geometrical dimensions and ply angles of the composite thin-walled tube was optimized to seek the optimal parameters by using Response surface method.Through the experiments and numerical simulation,we can find that carbon fiber reinforced composite thin walled tube structure has good energy absorption characteristics,further more,it can be optimized to get the optimal geometrical dimensions and layer design which has certain reference value for the vehicle collision safety and lightweight application.