Analysis of aerodynamic effects and load spectrum characteristics in high-speed railway tunnels

Abstract

To study the aerodynamic effects and load spectra caused by high-speed trains passing through double-track tunnels, this paper uses unsteady, viscous, compressible Navier-Stokes equations and the Re-Normalization Group k-ε turbulence model with sliding grid technology for simulation. A dynamic model test is carried out to verify the calculation method and grid. This study considers the impact of the three main factors of the tunnel aerodynamic effect when the train passes through the tunnel. The peak of the aerodynamic load spectrum when the train is coupled to the tunnel is mainly concentrated in the range of 0–5 Hz. The results show that as the train speed increases, the peak pressure and pressure gradient increase significantly, and the maximum pressure gradient appears in the time between the peak and trough of the head wave. When two trains meet in the middle of the tunnel, the peak pressure and its position change significantly, and the maximum pressure gradient peaks reach 80.58 kPa/s. When two trains exit the tunnel, the pressure presents a fixed period of fluctuations, and the maximum pressure peak is only 0.09 kPa less than the peak when a single train passes through the tunnel at the same monitoring point.