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Publications in Scientific Journals:

H. Sockel:
"Aerodynamic effects caused by a train entering a tunnel";
PAMM, 1 (2002), 1; 268 - 269.



English abstract:
The entrance of a train head in a tunnel causes a pressure wave with a steep gradient followed by a further, but less steep increase of the pressure due to friction on the train and tunnel wall, respectively, caused by the entrance of the train body (Fig. 1). This pressure increase is terminated by the entrance of the tail of the train causing a rarefaction wave, if the tunnel is long enough, so that there are no in.uences of reflected waves from the opposite tunnel portal. Since pressure transients in a railway tunnel may cause inconveniences to passengers and tunnel workers, respectively, it is important to have a reliable method for calculating the pressure history of a train passing a tunnel.
Results from full-scale experiments show only minor variations of the pressure over the cross-section of the tunnel, if the measuring point is not too close to the entrance portal. Therefore CFD-programs for viscid flow onedimensional in space give rather reliable results. Such programs are applicable for the whole passage of one or more trains through a tunnel at the same time [1].
The pressure history of a passage of a train through a tunnel is dominated by the propagation and reflection of the wave of the first pressure increase due to head and body entrance. It is important to estimate these effects as simple as possible and to show the influences of the main parameters like Mach number and blockage ratio. A rather simple formula is given for the first two pressure peaks and the results are compared to results from CFD-calculations.


Electronic version of the publication:
http://www3.interscience.wiley.com/cgi-bin/abstract/92013340/ABSTRACT


Created from the Publication Database of the Vienna University of Technology.