Temperature Rising by a High-Speed Train Running through a Long Tunnel

A significant amount of thermal energy is given off in the tunnel when a high-speed train is running through a long tunnel, and only few of thermal energy generated from this case shall be brought out of the tunnel by the train. The thermal energy is the result of dissipation caused by aerodynamic drag, mechanical resistances, and inefficiencies in the power unit. In this paper, heating of aerodynamic drag are calculated in terms of pressure drag and friction resistance as well. Heating of auxiliary equipment, train equipment, train braking and pantograph electric arc etc. has also been comprehensively considered, and the energy loss of heat conduction induced by tunnel wall has been taken into account. As a result, the temperature rising in the long tunnel is generated and the result can provide us with a useful reference for design of the long tunnel for the high-speed train and its traction capacity.