Study Of Effects Of The High-Speed Railway Tunnel Shaft Shape And Area On Aerodynamic Effect

With the development of the high-speed railway, the effects of the aerodynamics become more and more important when train entering a tunnel. Under high-speed running conditions, the requirement for the tunnel mostly is aerodynamics. The transient pressure peak value, the pressure gradient and the export micro pressure wave are the major impact factor, which decide directly the train passengers' comfortable as well as the tunnel exports environment question. Therefore, In order to meet the need of our country railroad's development, lucubration of tunnel aerodynamic effect's mechanism and corresponding alleviation measure is very necessary.Prevenient study have proved that micro pressure wave value is proportional to the pressure gradient which the compression wave arrive the tunnel exports. So the basic golden rule of mitigation measures of micro pressure wave is reduced compression wave pressure gradient. It's an economic and efficient measure which adopt ventilation shaft to relieve aerodynamic effects, because these facilities usually must be constructed when constructed the large tunnels, so for long tunnels, we can adopt ventilation shaft and inclined shaft which constructed with the tunnel to relieve aerodynamic effects.This article mainly analysis the change rules of flow field when high-speed train crossing the tunnel which have ventilation shaft, Preliminary analysis the mechanism in theory which the high-speed railway tunnel ventilation shaft affects the aerodynamic effects, and to further study the effect of the high-speed railway tunnel shaft shape, area and the linking forms on aerodynamic effects. Trying to give the best composite forms through numerical simulation to different conditions.With the help of the numerical simulations, different shaft shape, area and the linking forms were investigated. The conclusion of the best shaft shape, area and the linking forms is meaningful in a particular context. Different tunnel length and train speed will make the best shaft shape and area changed, otherwise, different shaft position and numbers will also have great impact on the aerodynamic effects.