Structure Optimal Design Of The Car Front Door Impact Beam

With the development of china automobile industry and the increasing number of automobile, the trend of impact accidents caused by automobile in all kinds of traffic status is raising. And the side impact is one of the most frequent traffic accident, which is also one of the accident that cause the most casualty. The side of automobile is weak because its side is door. So the side-door impact beam is optimized, which can improve stiffness of the door, enhance the safety of side impact of car. And also can protect the occupiers and improve the safety of traffic.The Finite Element Method is applied to optimize the side-door impact beam of the car's front door. And validate it by putting the optimized beam into the front door model.Firstly, according to the requirement of the Federal Motor Vehicle Safety Standards intensity test of side door (FMVSS214), the simple model that the side-door impact beam impacting with the rigid pole is set up. Keeping the mass of beam unchangeable, its crashworthiness is improved by changing the shape of the cross-section. Put up three shapes of the section: squareness, U shape, double U shape, the cross-section is optimized by changing the slantwise angle of the wall, the length of the sunshade and the shape of the sunshade. By comparing with the evaluating parameters of the beam's crashworthy capacity (the absorbing energy at 152mm displacement and the peak value of the impacting force), the best one is gotten from above.Then, the model of the car front door impacting with rigid pole is builded. Out of the door model, one rigid frame system is added, which can simplify the model, at the same time, the whole car impacting with rigid pole in real condition can be simulated well by using the system. Which offer a new idea to the simplifing model that car door side impacting with others.After caculating, the crashworthy analysis to the door is carried through, and the beams optimized are put into the door model, by comparing with the door fixing the primary beam, the crashworthiness of the structures after optimized are improved more or less, and the contrastive crashworthiness result of the optimized beams is consistent with the result gotten from the simplified model. So the rationality of the optimizing method and the simplified model is validated.The crashworthiness of the front door and the whole car's side can be improved by optimizing the side-door impact beam and finding the best structure in certain range. In addition, the best cross-section gotten from the simulations is more universal, and can be extensively used in any side-door impact beam of various automobiles.