Analysis And Structural Optimization Of Energy Absorbing Properties Of Foam Filled Composites

With the rapid development of society,people's living standard is also rising,the world per capita car ownership has also been improved,with car accidents are more,so as to improve vehicle safety becomes more and more important.In addition,under the premise of ensuring safety,lightweight has been the theme of the automotive industry,to reduce emissions and performance improvement,energy strategic planning and the healthy development of the automotive industry are of great significance.The application of the new structure and material with light weight and excellent energy absorption performance is an important means to realize the lightweight and improve the safety of the vehicle.In this paper,a new structure of carbon fiber reinforced polymer(CFRP)filled with polyurethane foam(PU)was proposed,and its structure was analyzed and optimized.First of all,The basic parameters of mechanical properties of PU foam and CFRP were obtained by material property test.At the same time,comparative analysis of LSDYNA material models,and find a suitable model for the simulation of PU foam and CFRP.Secondly,using Hypermesh software for pre-processing Quasi-static compression of the CATIA model of CFRP cone table,CFRP conical shell and PU foam filled CFRP cone.Using LS-DYNA to solve K file which exported from Hypermesh.Then,make the same size as the finite element model to experimental analysis.The results show that simulation results are in good agreement with the experimental results.The correctness of the finite element model and the material model of the composite filled structure is verified.The results showed that the foam filled CFRP cone tube had a good energy absorption ability,and the filling structure has higher specific energy absorption than that of the two materials used alone,but the effective energy absorbing stroke of the filling structure is reduced.Finally,in order to improve the energy absorbing ability of the cone shaped energy absorbing structure,In this paper,increasing the effective energy absorbing stroke and changing the half angle of the conical structure were brought up.In order to improve the efficiency of energy absorption,this paper presents a hollow structure filled with conical structure,and it is found that the hollow structure can effectively improve the energy absorption capacity of the structure.It is found that the effective energy absorption capacity of the structure increases with the decrease of the half apex angle.At the end of this paper,the cone filled hollow structure is optimized by taking the thickness of PU foam and the radius of the upper end of the cone as variables,and the maximum energy absorption and the minimum mass as the objective.