Lightweight Design And Crashworthiness-research For Front Door Beam Of Car Body

The study of automobile lightweight and crashworthiness can push the sustainable development of automobile industry. With the rapid development of composite material and gradually increase of performance,composite material as an effective way to realize automobile lightweight also will be used wider and wider in automobile body structure.Object of this research is the car’s bumper beam, which plays an important role of side door protection system. Starting from the material nature, the paper apply carbon fiber/epoxy composite in the automotive bumper beam,which has been widely applied in the study of automotive lightweight, combining with the FMVSS 214 regulation, the research can be described as follow:(1)Combining with the FMVSS 214 regulation,established automobile side impact finite element models with high-tensile steel and composite material. Through the systematic comparison and analysis of impact force it has borne, collision of displacement,energy absorption of the door protection system and so forth,tested the crashworthiness of the two different materials side door bumper beam.(2)According to the two materials side door anti collision beams changes during the simulation process,combining with the characteristics of composite materials,put forward a variable thickness design method for side door anti collision beam,that is to design separately of the thickness according to different position of anti collision beam strength demand.(3)Take side door anti collision beam cross section’s thickness and thickening of the length as variables, using the optimization method of Kriging surrogate model to build anti collision beam quality and crash box surrogate model, and use the NSGA- II algorithm for multi-objective optimization. Then compute the optimal solution set of Pareto and select a set of quality and thickness of anti collision beam most close to the optimal solution and anti-collision beams with uniform thickness contrast analysis,take anti-collision beams thickness as parameter, intrusion measurement,the collision force and anti collision beam energy absorption during side crashing as criterion,to check its crashworthiness.The results show, the design of variable thickness can improve the size of the collision force that anti collision beam bears, ensure that even though anti collision beam weight remains the same,the crashworthiness could also being greatly improved.