Aerodynamic Optimization of Nose Configuration for Reducing Pressure Variation at Train Passage.

Abstract

A numerical algorithm to optimize the nose configuration of train is developed to reduce the pressure variation caused when a train runs. A pressure field is generated around a moving train, which is viewed as a pressure variation by an observer on the ground because it moves with the train. Since the pressure variation when a train runs is closely related to the form of train nose configuration, its improvement is one means of reducing the pressure variation. In this algorithm, the train nose configuration is designed to minimize the peak-to-peak value of static pressure around the train by using the Stokes stream function for axisymmetric flow combined with nonlinear programming. An optimized train nose configuration can be obtained in a very short CPU time with a 6% smaller peak-to-peak value of pressure variation. In addition, experiments using models corresponding to the case under consideration have been carried out to confirm the numerical validity. The results indicate that this algorithm is efficient in designing the train nose configuration with smaller pressure variation during train operation.