A Cooperative Optimization Method of Electric Field-Flow Field for Roof Insulators of High-Speed Trains

Aerodynamic drag generated during the high-speed train operation not only lowers operating efficiency and increases power consumption but also restricts the speed for further improvement. As the existence of roof external insulation equipment, the aerodynamic drag on the roof increases and the optimization of drag reduction for it is an essential development trend. In this article, a simulation model for the external insulation equipment is first established and validated. Also, a cooperative optimization method of electric field-flow field of roof insulator based on micro-macro bionic structure is proposed. Second, the datasets, including eight input parameters and two output parameters, are collected. Four surrogate models are constructed and compared to determine the preferable model. Then, the optimal structural parameters are obtained using the multiobjective particle swarm optimization (MOPSO) algorithm. The flow field and the electric field of roof insulator before and after optimization are analyzed. Finally, the 3-D printed insulators are employed to verify its insulation performance. The results show that the optimized roof insulator can achieve 21.33% drag reduction. The average electric field strength decreases by 8.19%, and the flashover voltage is significantly improved. The cooperative improvement of aerodynamic drag reduction-insulation performance of the roof external insulation equipment is realized.