A Study On The Compatibility Of Sedan-to-SUV Frontal Crash

Many studies have shown that frontal collision were the most major accident. Itwill definitely cause a high casualty if a sedan impact against a SUV. Therefore, thecompatibility between sedan and SUV has become a hot research topic and is of greatsignificance. The paper was carried out according to the following aspects:1. A brief introduction of the compatibility in domestic and international statuswas described. And the parameters that described stiffness and geometry werepresented.2. The FE models of the vehicles that used in this paper were developed byLS-DYNA according to US-NCAP. By comparing the acceleration of the car body anddeformation modes of key part, the simulations fit the experiments well. Thisguarantees the accuracy of the FE models.3. The mass ratio was changed by adjusting the weight of SUV; the AHOF400mismatch was changed by varying the height of SUV; the Kw400ratio was changedby adjusting the stiffness of longitudinal. Then the FE models of different mass ratio,AHOF400mismatch and Kw400mismatch were developed in different overlap rate.Absorb energy, intrusion of toepan in sedan and intrusion of A-pillar was chosen asparameters which determine the compatibility. Compared with the original models, itshows that these three factors have a strong impact on compatibility. Besed on thesimulation analysis, the suggestions of improving compatibility by modifying thestructure were proposed.4. According to the previous analysis, a proposal of improving compatibility byadjusting the structure of sedan and SUV were presented. The simulation result showsthat the modification of vehicle structure could strongly improve the compatibility.In the end, the evaluation of car safety and compatibility was carried out by thesimulation of US-NCAP full wide rigid barrier impact.The results of this paper show that: The structure interaction characteristicsof the two vehicles involved incollisions are affected by the overlap ratio. Theverlap ratio is another key factor contributing to frontal crash compatibility.Frontal crash compatibility can be improved by regulating the vehicle frontstiffness and geometric characteristics reasonablely. The improvement ofstructure interaction effect of the vehicle front-end primery energy-absorbing components could is the crucial matter for compatibility improving. Thedistribution of collision energy between the two vehicles could be regulatedeffectively by reducing the stiffness ratio of the two vehicles. The aggressivity ofthe large vehicle could be reduced by softening its fron-end structure. Howeverthe reducing of the front-end stiffness of the vehicle would affect itsself-protection standards. So compatibility reaserch should consider the vehicleself-protection standards.