Research On Analysis Method Of Tire Grip Performance And Its Relationship With Tire Crown Structure

With the rapid development of auto industry, the number of traffic accidents is taking on the increasing trend, more attention has been paid to the safety of the car. Braking performance has been considered as a critical issue on vehicles safety. The EU tire labelling regulation and the Green Tire Technology Specification published by Chinese government have put forward clear requirements and specific implementation deadlines on tire grip performance. Tire is the only part of vehicles that contacts with the ground, so the tire crown structure has directly affected on the grip performance. In order to cater into the requirements of the regulation, it has important theoretical meaning and engineering application value to develop tire grip performance simulation method and the influence of tire crown structure on grip performance.The friction experiment was carried out on the friction-wear experimental. The friction coefficient of tread rubber was tested under different pressure and slip velocity. Thereby a friction model was put forward to describe the tread rubber friction behavior under various contact conditions. The user subroutine FRIC_COEF provided by ABAQUS was used to develop the friction model. In addition, a finite element model was established to simulate the test procedure, which verified the effectiveness of the friction model via the good agreement between the computed friction torque and experimental results.Taking the all steel TBR tire 295/80R22.5 as the research object, the tire finite element model was established. The friction model put forward in this paper was selected to describe the contact behavior at the tire-pavement interface. Anti-lock brake system(ABS) process was achieved by controlling the tire angular velocity to obtain the relationship between friction force and slip rate, while the maximum friction forces were used to evaluate tire grip performance.In order to improve tire grip performance, the tread arc and pattern layout were selected as the design variables, the structural optimization approximation model based on the RSM(Response Surface Method) with the objective of maximizing the friction force between tire and road was built up in this thesis. Then, the optimization model was optimized by the genetic algorithm and the wear performance of optimized tire structure was analyzed. The results show that the friction force has a rising trend when the center rib width has been increased; the shoulder rib width and tread arc have been reduced. The optimized tire structure can improve the grip performance by 2% without reducing tire wear performance. Then, the relationship between the grounding characteristic parameters and grip performance was analyzed, which provided a feasible way for tire structure design.To study the effect of tire pattern structure on grip performance, the braking process of tire pattern was simulated, which the boundary conditions of local model are derived from the results of the whole tire model. The grip performance of tire pattern was evaluated by the friction force. The significant influencing on grip performance of tread pattern grooves parameters was investigated. In addition, the bionic lateral pattern design idea was put forward to realize the improvement of grip performance. Meanwhile it provided a new way of thinking for the further development of the tire pattern design.