Numerical and experimental investigations of the flow around a high-speed train on an embankment under sidewind conditions

Abstract

In this paper the aerodynamic forces and moments on a high-speed train in a cross wind were obtained both numerically and experimentally. The train was positioned at the top of a 2m high embankment. Experimental data was obtained using the Monash wind tunnel for a 1:20 scale model. These measurements were made over a range of yaw angles spanning 0◦–90◦. The numerical computations were performed using the commercial code FLUENT. These computations focused on the structure of the flow field around the high-speed train at different yaw angles. The model was discretized using a hybrid grid, with a total cell count of 1.02×107. The predictions showa good match for the calculated aerodynamic force and moment coefficients with experimental measurements. Aerodynamic forces were determined for two cases: with the train on either the windward or the leeward track on top of the embankment. The side force is found to be greater for the leeward case, while the lift force for the leeward case is less than that for the windward case.