A generalised flow prediction method for the unsteady flow generated by a train in a single-track tunnel

A Generalized Numerical Simulation Method for Pressure Waves Generated by High-Speed Trains Passing through Tunnels

“…The irreversible effects are considered and they are: (1) train and tunnel friction, (2) heat transfer between the tunnel and the air, and the train and the air, and (3) mass transfer through the sides of the train due to pressure differences. It is one of the most perfect one-dimensional flow models for investigating airflow in tunnels: it can accurately simulate the pressure excursion and the air temperature change in the tunnel (Woods, et al 1981). Since the 1970s, based on this model and the method of characteristics of generalized Riemann variables, Woods et al have developed a program which can be used to calculate the pressure waves caused by a single train passing through a tunnel.…”

“…The governing equations of a one-dimensional, compressible, unsteady, and non-homentropic flow model are (Woods et al 1981;Mei 1997): Continuity equation:…”

Experimental 3-D Simulation of the Compression Wave, Due to Train–tunnel Entry

“…The most important parameters affecting the abovementioned pressure wave are the train Mach number M, the train/tunnel blockage ratio S Train =S Tunnel (train nominal cross-sectional area divided by the tunnel nominal crosssectional area), the train nose geometry and the tunnel entrance geometry. It has been proved that the maximum value of the compression wave amplitude increases with the train speed squared, and that of its temporal derivative and the micro-pressure wave amplitude vary approximately with the train speed cubed (Swarden 1973;Ozawa 1979;Woods & Pope 1981;Kage et al 1992;Iida 1994;Auvity & Kageyama 1996;Howe 1998a). Moreover, when the initial pressure gradient of the compression wave is high enough, it can increase along the tunnel (Ozawa 1979;Aoki et al 1995) because of the compressibility of the air and the adverse effects become more severe.…”

Numerical Simulation of Air Flow Properties around a Train Body in Long Tunnel Space

“…Air pressure will be changed frequently; wind which is induced by train will be amplified; aerodynamic drag will be increased several times and disturbing of aerodynamic noise will appear in long tunnel. W.A.Woods [1] investigated a generalized one-dimensional flow prediction method for calculating the flow generated by a train in a single-track tunnel. Raghu S. Raghunathana, H.-D. Kimb, and T. Setoguchi [2] indicated the aerodynamics of high-speed railway train.…”