Research On Crashworthiness Analysis And Structural/Material Optimization Of SUV Frame

With the continuous development of vehicle ownership,the safety of vehicle collision has been more and more concerned by people.This paper improves the collision performance of separate frame construction vehicles,and comprehensively considers the lack of collision ability of vehicles and the loss weigh issues from both structural and material aspects.Innovative addition of new foam aluminum materials to the frame,the purpose of which is to give full play to the unique energy absorption characteristics of the foam aluminum filling structure,and optimizing the size of the frame to ensure the safety of the collision.It provides a brand-new design idea for the collision safety design of passenger cars in China.(1)The theoretical analysis of the collision deformation and energy absorption transmission of the whole vehicle is carried out.The differential ideology is used to further explain the deformation of the frame.The theory of mass conservation and energy conservation is used to further study the collision process of the vehicle.Derivation provides the basis for subsequent optimization design.The actual vehicle collision and the simulated collision are benchmarked,which proves that the accuracy of the vehicle simulation and the collision safety of the vehicle are insufficient.(2)Based on the basic theory of sensitivity,the sensitivity of the nine components of the frame are analyzed by using the node displacement of the anti-collision steel beam,the collision energy absorbing box and the longitudinal beam as the constraint.Then,the thickness of each component of the frame is used as the design variable.The lightest quality is the iterative calculation for the objective function.The results show that the frame is further reduced by 5.3kg when the frame meets the design requirements.Afterwards,the unique characteristics of the foamed aluminum material were explained from the three aspects of physical properties,mechanical properties and energy absorption properties.The processing technology of foaming the substrate into the longitudinal beam shell of the frame was determined.(3)The simulation calculation of the foamed aluminum filled in the frame of the longitudinal beam of the frame is carried out,and the simulation data is compared with the original frame simulation data.The results show that the optimized frame deformation is smaller than the original frame;the optimized vehicle the maximum collision speed in the X direction is 10ms earlier than the maximum collision speed of the original frame;the maximum speed node of the frame is-0.32mm/ms after optimization,which is 83%lower than the original frame;the maximum collision of the frame The acceleration is-3.7e~5mm/s~2after optimization,which is 18%lower than the original frame;The speed of each node of the frame is more gentle than that of the original frame.After optimization the maximum node displacement of the frame is 255mm.The original frame was reduced by 28%compared with the optimizationl frame;The frame beam member had a total energy absorption of 210.3KJ,and the energy absorption rate was increased by 26.3%compared with the original frame.The optimized longitudinal beam filled foam aluminum frame can greatly improve the collision safety of the whole vehicle.