Multidisciplinary Optimization Of Railway Wheel Web Shape Based On Intelligent Algorithm

With the development of high-speed railway and the improvement of the railway freight transport technology, the requirements for the train running performance are also increasing. As one of the most important parts of the safety and stable operation of the train, the design of train wheel is very complicated. It involves many subjects such as the wheel/rail geometry, contact mechanics, wheel/rail noise, wheel/rail dynamics. The mechanical stress, thermal stress and radiation power generated by the wheel in the operation are closely related to the geometry of the wheel spoke plate. The design and optimization of the wheel spoke plate has attracted much attention of the industry and the scholars. However, the traditional optimization studies are mostly carried out separately in the mechanical performance or the vibration and noise. With the coupling effect between the different subjects, the traditional design method can not meet the needs of the development of the industry.In this paper, the numerical simulationof mechanical stress field, thermal stress field, vibration sound radiation and multidisciplinary design optimization theory are combined. Based on the analysis of the inter relationship between subjects, using the calculation method of "experimental design+approximate model" and the optimization of the algorithm, the optimization of the model is discussed. The main contents are as follows:(1) The calculation principle and calculation method of the mechanical stress, thermal stress and radiated noise of the wheel during operation are studied. The feasibility of the method is verified by a numerical example.(2) Based on the analysis of genetic algorithm and fish swarm algorithm, genetic algorithm and fish swarm algorithm are combined, and the search ability of genetic algorithm is used to search the global search, and the maximum step size and perceived distance are adjusted. Through the test function, it is concluded that a single genetic algorithm converges slowly, and a single fish swarm algorithm is easy to fall into local optimum, while the adaptive fish genetic algorithm is more easy to get the global optimal solution, and the results are more stable, better robustness and faster convergence.(3) The calculation method of the "experimental design+approximate model", and the test method of the approximate model accuracy, and the MATLAB program of the test design method and the approximate model are developed. Through three test functions, the Surface Methodology Response (RSM) model, Kriging model and Basis Function Radial (RBF) model are analyzed.(4) Using "experiment design and approximation model" method of heavy haul freight car wheel of thermal-mechanical coupling optimization design, to meet the static strength and fatigue strength as constraint, wheel quality decreases as the optimization objective, using fish adaptive genetic algorithm optimum calculation, find the optimal solution. In addition, the B spline curve is used to construct the shape of the wheel spoke plate, and the design space of the web plate is enlarged, and the model is also reduced. The optimal scheme is 7.62% lower than that of the original scheme, and the braking thermal stress is reduced by 31.3%, and the maximum Mises Von stress is reduced by 2.3%.(5) The multi-discipline and multi-objective optimization design method for the wheel of high speed train is proposed. The multi subject model of high speed train is established according to the method of "experimental design and approximate model". Through the AMGA algorithm, the model of three typical Pareto solutions is compared and analyzed. The three models have different degrees of improvement in the overall performance, the quality of which is 4% and the highest is 13.86%.(6) The mechanical stress field and the vibration noise of the wave plate wheel are studied. The model of the wave plate with different wave numbers and different wave amplitude is established. The mechanical stress field and sound radiation power of the wave plate are analyzed in detail. The 6 wave radiation is obtained. Using the method of multi-discipline, the problem of multi-objective problem into single objective optimization is obtained by using linear weighted method, and the results are compared with the results of 5 schemes.