Numerical simulation research on related problems of tunnel ventilation at entrance of long and large tunnels

For the emergency rescue station at the entrance of the long and large railway tunnel, adopts the tunnel entrance ventilation method to avoid the direct exposure of the fan in the tunnel and reduce the risk of tunnel operation due to the operation of the fan. Taking a long and large tunnel as an example, studies the related problems of tunnel ventilation by using CFD numerical simulation, and obtains that the double-sided air supply of the tunnel entrance has a better ventilation effect. Further studies the double-sided air supply, and the results show that when the air duct spacing is twice the equivalent diameter of the main tunnel, the air supply velocity at the tunnel entrance is larger and the velocity nonuniformity coefficient is smaller.