Structure Analysis And Optimization Research Of Urban Railway Wheel Based On Thermo-mechanical Coupling

Urban railway wheel is not only an important supporting body of the vehicle, but also bear the force of braking and the static, action force of the rail. The force of the wheel is complex extremely. Besides, with the continuous improvement of the efficiency of the urban railway operation and the continuous increase of passenger capacity, the brake of urban railway become more frequently, causing the force of the wheel more complex. In order to improve the intensity of urban railway wheel, the structural analysis, thermal analysis and optimization of innovation of urban railway wheel is an important and difficult in the study of urban railway wheel for a long time. As a consequence, the strength analysis of urban railway wheel not only has a certain guiding significance to the maintenance work, but also has an important reference value to the design of urban railway wheel.The contents of the paper can be listed as follows:(1) An urban railway wheel model was established. The calculation method of structure load and thermal load of the urban railway wheel were given. The feature of mechanical stress and thermal stress of wheel under the different abrasion were studied. And the superposition rule of the mechanical stress and the thermal stress is obtained under the thermo-mechanical coupling condition. The results of simulation show that the changes in the mechanical stress, the thermal stress and the thermo-mechanical stress are nonlinear with the development of surface wear tread of rail wheel; The thermo-mechanical stress of urban railway wheel is produced by the superposition of complex three dimensional force system, and the thermo-mechanical stress plays a leading role on the wheel stress.(2) Three kinds of typical plate(straight plate, single S plate and double S plate) urban railway wheel models were set up. Focusing on the thermo-mechanical coupling performance of the three types of plate wheel under emergency braking, the antifatigue characteristic of the thermo-mechanical coupling stress is obtained under the thermo-mechanical coupling condition. And the Goodman fatigue limit diagram was drew for evaluating the new wheel and wear to limit wheel of the three kinds of urban railway wheel. The results show that the three kinds of urban railway wheel can satisfy the requirements of fatigue strength. And the double S plate wheel has a better anti-fatigue performance than straight plate and single S plate wheel in the coupling field.(3) In order to improve the comprehensive performance of the double S plate wheel, the structure characteristic of the double S plate wheel was studied. Considering the thermo-mechanical coupling, several thoughts of double S plate wheel optimization models were analyzed. The key parameters of double S plate wheel plate were optimized by the method of orthogonal experiment. At last, the Goodman fatigue limit diagram was drew for evaluating the optimized wheels. The results show that the double S plate wheel has a good safety performance when S bending in the positive direction and arc in the center position. The plate thickness and the radius of arc near the rim have a greater influence on the performance of the double S plate wheel. Besides, the optimized wheel can satisfy the requirements of fatigue strength.