Optimization of Underground Rail Top Wind Channel Based on CFD

Aiming at the situation that the heat discharge efficiency of rail head duct in subway station is low, a scheme to release the space at the top of the track to enhance the heat discharge effect is proposed. The flow field model at the top of the track is established and the parameters such as flow field and temperature field are calculated by numerical simulation. The simulation results show that cancelling the rail top exhaust air has a better effect on the thermal environment of the tunnel than shutting down the rail fan, but the overall temperature field is still too high. Therefore, the optimization strategy to change the exhaust parameters is selected: reduce the overall size of the rail top exhaust outlet distribution, and appropriately move the position of the exhaust outlet to the driving direction. The specific thermal efficiency evaluation parameters of the optimization scheme are put forward, and the effect of the optimization scheme is verified by numerical simulation. The research results show that the heat discharge efficiency of the rail head duct can be increased by about 25% ~ 40% after the optimization scheme is adopted in this paper.