Drag Optimization of the High-Speed Train Head using the Response Surface Method

摘要

In order to reduce the aerodynamic drag force of a high-speed train, an effective automatic optimization design method for the streamlined head of a high-speed train was established, and the optimization design for the drag reduction of the streamlined head of the high-speed train was carried out. The three dimensional parametric model of the streamlined head of the high-speed train was set up and five optimization design variables were extracted. The optimal Latin hypercube design method was used to obtain the uniform sampling points from the design space of the optimization design variables. The corresponding aerodynamic drag forces of the high-speed train were computed using a computational fluid dynamic method. The approximate computational model between the optimization design variables and the aerodynamic drag force of the high-speed train was set up using the response surface method. The error between the actual value and predictive value of the aerodynamic drag force is less than one percent, which meets the requirement of the engineering computational accuracy. In the process of the optimization, the aerodynamic drag force of the high-speed train was computed using the approximate computational model, the automatic update of the optimization design variables were achieved using the multi-island genetic algorithm. The computational time of the optimization is greatly reduced. All optimization design variables and the aerodynamic drag force show a trend of convergence with repeated iterative computation. By contrasting the aerodynamic drag force of the original streamlined head, the aerodynamic drag force of the optimized streamlined head was reduced by 3.643 percent.