Research On Vehicle Frontal Impact And Anti-collision Structure Energy Absorption

With the rapid development of Auto Industry in China, vehicle safety is getting moreand more attention. The frontal thin-walled structure is the most important part during thefrontal impact, which is highly possible during collision. Therefore, how to improve thethin-walled structure to increase energy absorbing and reduce impact peak force, is one ofthe most important research areas.On the basis of literature review in the area, a whole vehicle frontal collision FEAmodel was established and analyzed through HyperMesh and LS-DYNA software, toevaluated its performance in energy absorbing. Results showed that the frontal energyabsorbing was49.78%, which was lower than the regulation (50%). It was indicated thatmodification was needed in the frontal portion. And, even the deformation of thin-walledmet the gradient sequence in the process of collision, further optimization was needed dueto the incomplete compression of longitudinal beam.Then, research was conducted on the bumper and the front longeron component todiscuss the impacts of structure change on energy absorption performance. For frontlongeron, inducing grooves number, interval and arrangement pattern were taken intoconsideration. For the bumper, the thickness of the inner and outer plate, material andstructure type of beam were taking into consideration. The simulation results showed that,adding the number of grooves can increase fold number and reduce the peak impact force.Decreasing the interval of grooves can increase the thin-walled beam energy absorptionand improve the vehicle collision performance, and the deformation performance ofthrough-type groove was better than non-through-type. Material and thickness increasingof the bumper beam can improve the crashworthiness of the bumper. Besides, inside thebumper hollow part adding reinforcing plate can effectively reduce the collisionacceleration. Finally, orthogonal optimization method was used to optimizing the combination ofnumber of inducing grooves on the front longeron, interval of inducing grooves on thecrash box, bumper beam thickness and material. The obtained optimal solution was thenanalyzed in the whole vehicle model. Results showed that the energy absorbing increasedto51.1%, and column B acceleration decreased to3.47g, which illustrated the structuremet the requirement of regulation.