Investigation of the Tunnel Passage of Coupled Trains

Abstract

The aerodynamic drag experienced by trains in tunnels is significantly higher than in open space. This applies in particular to new single-track, twin-tube tunnels with a relatively narrow cross-section. A special situation arises when two trains pass through a tunnel relatively close together, as is the case with virtually coupled trains. This raises the question of how the aerodynamic resistance of the two train sections compares with that of directly coupled train sections or a uniform single train of the same length.