Numerical Simulation On Unsteady Flow Characteristics Around High-speed Train In Tunnel

When high-speed train through the double-track tunnel, due to trains and tunnels formed asymmetrical space, the flow of characteristics also asymmetrical, and makes effect on the pressure characteristics of the tunnel wall and the train surface naturally different, eventually leading to the train in the tunnel runtime lateral vibration intensified, threatening the stability and security of train, so it has very important significance for study on the flow field in the tunnel outside the train.This article is based on the German ICE2 high-speed train and domestic CRH380 A high-speed train model, using RANS, URANS and LES three different numerical simulation method, to establish a reasonable grid generation strategy, using finite volume method of software STAR-CD, high-speed train inside the tunnel external unsteady flow field numerical simulation.Considering the computing resources and the time limit, this paper studies the internal and external unsteady flow field of the external Reynolds number is 51?10.This paper analyzed the flow field of high speed train passing throng double line tunnel using numerical method, preliminarily established methods of large eddy simulation computation settings and post-processing details, providing the reference for changing train models in the future. Analyzed pressure, vorticity contour, Q value and The lateral force coefficient and lift coefficient of typical section, pointed out surface and trains around pressure distribution and the position of the vortex structure and law of development when ICE2 was passing the tunnel. And analyzed the causes of transverse vibration when the train was running in the tunnel. Then based on the experience of ICE2 calculation model, numerically studied external flow field characteristics of the CRH380 A high-speed train passing through the tunnel, using multi piece of grid technology and reduced the number of the grid, improved the calculation efficiency. Analyzed pressure, vorticity contour, Q value and The lateral force coefficient and lift coefficient of typical section, pointed out surface and trains around pressure distribution and the position of the vortex structure and law of development when 380 A train was passing the tunnel, and compared and analyzed the results from calculation model for ICE2 and CRH380 A calculation. Finally analyzed the calculation results of three methods of numerical simulation, got the optimal method of numerical simulation.In this article, the external flow of ICE2 high-speed train and CRH380 A high-speed train in tunnel are simulated and analyzed. The computational results and laws can be foundation of unsteady flow on high-speed train and provide a reference for the design and operation of high-speed train.