Crashworthiness Optimization Of A Saden In Small Overlap Impact

Small overlap impact is one of the most common types of traffic accidents.While about one quarter of the victims were died from serious injurys among all the deaths associated with frontal road traffic accidents,which seriously damaged people’s lives and property.In order to effectively reduce or even avoid the possibility of severe damage to the occupant in a small offset collision,the mechanisms of small overlap impact should be studied,which forms fundamental knowledge for development and design of vehicle body optimization measures in small overlap impact.The objective of this study was to investigate the optimization scheme of the vehicle body under the small overlap impact via the applicaton of the finite element model of a sedan.A small overlap impact finite element model was developed and validated;dynamic responses of the sedan sustained small overlap impact were analyzed;the crashworthiness of the sedan associated with the small offset collision was determined.A simplified finite element model was established and validated;based on the collision energy distribution and the displacement guidance structure respectively,the crashworthiness of the passenger vehicle was optimized and the influence of the optimization scheme on the front collision were discussed.Firstly,a small overlap simulation model was developed based on finite model of a sedan.The structural crashworthiness of the simulation model was analyzed according to the crashworthiness investigation principle,which forms fundamental knowledge for optimizing the crashworthiness of the sedan.Then,a simplified finite element model was established to improve the simulation efficiency.In order to meet the energy absorption requirements,the collision energy absorption structure in the front of the vehicle and the steering and suspension system were optimized,stiffness of the passenger co mpartment was improved which was based on the principle of collision energy management mechanism.In addition,a lateral displacement guide structure was designed base on the principle of increasing the lateral displacement of the vehicle body and reducing the crash intensity of the passenger compartment.The orthogonal test method was used to match the performance parameters of the lateral displacement guide structure.Then,the study of displacement guide structure performance parameters effect on the crashworthiness of the vehichle was carried out.It demonstrated that the proper matching of lateral displacement guide structure parameters could effectively improve the crashworthiness in the small overlap impact.Finally,the finite element model of the 100% frontal overlap rigid barrier crash test and the 40% offset collision were established on the basis of the optimization model.The vehicle acceleration,steering column intrusion,front door deformation and firewall intrusion were analyzed.The influence of the optimization scheme on the front collision were discussed.