Dundee Tunnel Research

ThermoTun Validation - Full Scale Tests

In the 1970s and 1980s, the British and German Railways compared measurements with predictions of an early version of ThermoTun, then called 'AeroTun'.

Glöckle & Pfretzschner (1988) showed that AeroTun could predict pressure fluctuations alongside two trains crossing in a short tunnel with high accuracy. Importantly, they showed good agreement during the period when the trains crossed as well as before and after this period. The illustration in their paper deals with a case where inertia is dominant and the pressure histories are dominated by strong, short-lived events.

The same authors also showed that the program underestimated the degree of attenuation of pressure waves propagating in long tunnels. Deutsche Bundesbahn subsequently funded a research program at the University of Dundee to understand the causes of this problem and thereby began a long-standing study that is finally leading to practical methods of simulating the phenomenon.

Vardy (1980) reported comparisons with measurements undertaken in the London Underground. The principal purpose of the paper was to assess the level of detail that needs to be considered when predicting pressure histories in tunnels of complex geometry.

Later, Vardy & Reinke (1999) reported comparisons with measurements undertaken by DB AG in the Grauholtz Tunnel in Switzerland. The primary purpose of the paper was to demonstrate the feasibility of deducing train resistance parameters from measurements of trains in routine service.

Hagenah et al (2006) described pressure measurements inside and outside trains during commissioning tests on a new high speed railway. Airshafts had been provided in the tunnels with the objective of minimising overall construction costs whilst satisfying demanding pressure comfort criteria. The tests confirmed the compliance of the design.


Glöckle,H & Pfretzschner,P (1988) 'High speed tests with ICE/V passing through tunnels, and the effects of sealed coaches on passenger comfort', Proc 6th int symp on the Aerodynamics and Ventilation of Vehicle Tunnels, Durham UK, BHR Group, 23-44.

Hagenah,B, Reinke,P & Vardy,AE (2006) ‘Effectiveness of pressure relief shafts - full-scale assessment’, Proc 12th int symp on the Aerodynamics and Ventilation of Vehicle Tunnels, Portoroz, Slovenia, BHR Group, 379-391.

Vardy,AE (1980) 'Unsteady airflows in rapid transit systems'. Proc IMechE, 194(32), 341-356.

Vardy,AE & Reinke,P (1999) 'Estimation of train resistance coefficients in tunnels from measurements during routine operation', J Rail & Rapid Transit, Proc IMechE Part F, 213, 71-87.