Study Of Shaft Impact On Aerodynamic Effects Of The Two-lane High-speed Railway Tunnel

Obvious pressure fluctuation in tunnel and micro-pressure wave radiated from the exit of the tunnel,which are caused by a train entry into a tunnel at a high speed,will make serious negtive impact on driving safety, passenger comfort and environment around tunnel.Therefore,it is a crucial issue that must be considered when designing the high-speed railway-tunnel and improving existing tunnels to adapt to the speed-raising railway system.In this paper the high-speed train, Two-lane railway tunnel and ventilation shafts were studied.A combined method of numerical simulation and modle test was used to study the aerodynamic effects when the high-speed train runs across the tunnel with shaft.n order to truly simulate the complex airflow inner tunnel,the FLUENTL software and the technic of sliding grid were adopted. And then influences to tunnel aerodynamics by different areas and locations of the shaft were studied based on the three dimension incompressible viscous N-S equation and standardκ-εturbulence modle.The regularity of theShafts impact on aerodynamic effects of the high-speed two-lane railway tunnel was preliminarily given through theoretical and computational aerodynamic analysis.With better synthetic effect of the reduction of pressure amplitude and micro-pressure wave both on train surface and tunnel wall,optimum value of shaft section area and location in two-lane railway tunnel with single shaft in it.At the same time moving model tests in tunnel with several kinds of single shaft and double shafts were done adopting scaled model by using moving model experimenting system in Central South University, through which pressure results and micro-wave pressure results of corresponding measuring points were given.Regularities given from numeric calculation is identical to moving model experiment, which has proven the credibility of the numerical calculation.