Tire wear is a very complicated phenomenon that is influenced by various factors such as tire material, structure, vehicle and road conditions. In order to evaluate tire wear, a method for measuring tire wear using th...Tire wear is a very complicated phenomenon that is influenced by various factors such as tire material, structure, vehicle and road conditions. In order to evaluate tire wear, a method for measuring tire wear using the intensity of reflected light was presented?[1]. It comprises applying a single layer of reflected paint to a tread surface by spraying, and then measuring the intensity of light reflected from a matrix of blocks on the unworn tire. In this paper, a numerical technique for predicting the uneven wear of passenger car tire is presented. The uneven tire wear produced in wheel alignment condition with vehicle speed, camber angle, and toe angle is predicted by the frictional dynamic rolling analysis of 3D patterned tire model. The proposed numerical technique is illustrated through the method of paint testing the wear on the tread surface of a tire.展开更多
This paper develops a coupled dynamics model for a linear induction motor （LIM） vehicle and a subway track to investigate the influence of polygonal wheels of the vehicle on the dynamic behavior of the system. In th...This paper develops a coupled dynamics model for a linear induction motor （LIM） vehicle and a subway track to investigate the influence of polygonal wheels of the vehicle on the dynamic behavior of the system. In the model, the vehicle is modeled as a multi-body system with 35 degrees of freedom. A Timoshenko beam is used to model the rails which are discretely supported by sleepers. The sleepers are modeled as rigid bodies with their vertical, lateral, and rolling motions being considered. In order to simulate the vehicle running along the track, a moving sleeper support model is introduced to simulate the excitation by the discrete sleeper supporters, in which the sleepers are assumed to move backward at a constant speed that is the same as the train speed. The Hertzian contact theory and the Shen– Hedrick–Elkins’ model are utilized to deal with the normal dynamic forces and the tangential forces between wheels and rails, respectively. In order to better characterize the linear metro system （LMS）, Euler beam theory based on modal superposition method is used to model LIM and RP. The vertical electric magnetic force and the lateral restoring force between the LIM and RP are also taken into consideration. The former has gap-varying nonlinear characteristics, whilst the latter is considered as a constant restoring force of 1 kN. The numerical analysis considers the effect of the excitation due to polygonal wheels on the dynamic behavior of the system at different wear stages, in which the used data regarding the polygonal wear on the wheel tread are directly measured at the subway site.展开更多
文摘Tire wear is a very complicated phenomenon that is influenced by various factors such as tire material, structure, vehicle and road conditions. In order to evaluate tire wear, a method for measuring tire wear using the intensity of reflected light was presented?[1]. It comprises applying a single layer of reflected paint to a tread surface by spraying, and then measuring the intensity of light reflected from a matrix of blocks on the unworn tire. In this paper, a numerical technique for predicting the uneven wear of passenger car tire is presented. The uneven tire wear produced in wheel alignment condition with vehicle speed, camber angle, and toe angle is predicted by the frictional dynamic rolling analysis of 3D patterned tire model. The proposed numerical technique is illustrated through the method of paint testing the wear on the tread surface of a tire.
文摘This paper develops a coupled dynamics model for a linear induction motor （LIM） vehicle and a subway track to investigate the influence of polygonal wheels of the vehicle on the dynamic behavior of the system. In the model, the vehicle is modeled as a multi-body system with 35 degrees of freedom. A Timoshenko beam is used to model the rails which are discretely supported by sleepers. The sleepers are modeled as rigid bodies with their vertical, lateral, and rolling motions being considered. In order to simulate the vehicle running along the track, a moving sleeper support model is introduced to simulate the excitation by the discrete sleeper supporters, in which the sleepers are assumed to move backward at a constant speed that is the same as the train speed. The Hertzian contact theory and the Shen– Hedrick–Elkins’ model are utilized to deal with the normal dynamic forces and the tangential forces between wheels and rails, respectively. In order to better characterize the linear metro system （LMS）, Euler beam theory based on modal superposition method is used to model LIM and RP. The vertical electric magnetic force and the lateral restoring force between the LIM and RP are also taken into consideration. The former has gap-varying nonlinear characteristics, whilst the latter is considered as a constant restoring force of 1 kN. The numerical analysis considers the effect of the excitation due to polygonal wheels on the dynamic behavior of the system at different wear stages, in which the used data regarding the polygonal wear on the wheel tread are directly measured at the subway site.
