Prediction of entry compression waves induced by a high-speed train entering tunnel

Tunnel wave produced by an entering high-speed train has always been one of the most prominent problems in the field of aeroacoustics. These waves are formed at the entrance of the tunnel and propagate ahead of the train at the local speed of sound. The formation process of the first of the successive compression wave at the entrance decides the nature and intensity of the subsequent waves. Thus, to visualize and understand the formation process; a numerical study has been conducted using commercial computational fluid dynamics (CFD) solver FLUENT 17.1. The dynamic mesh update techniques have been implemented to update the stationary domains as the train moves inside it. Pressure inside the tunnel is measured at distinct points to study the changes in the intensity of the compression wave. The flow physics has been comprehended using pressure plots and contours.