5. Ventilation Technology Management
A. For flexible ventilation ducts and spiral ventilation ducts with steel wire reinforcement, the length of each duct should be appropriately increased and the number of joints should be reduced.
B. Improve the tunnel ventilation duct connection method. The commonly used connection method of flexible ventilation duct is simple, but it is not firm and has large air leakage. It is recommended to use the protective flap joint method with tight joints and small air leakage, multiple protective flaps joint method, screw joint and other methods can effectively overcome this shortcoming.
C. Repair the damaged part of the tunnel ventilation duct and plug the needle hole of the tunnel ventilation duct in time to reduce the air leakage.
5.1 Reduce the wind resistance of the tunnel ventilation duct and increase the effective air volume
For the tunnel ventilation duct, a large diameter ventilation duct can be used to reduce various wind resistance of the tunnel ventilation duct, but the more important thing is to improve the installation quality of the ventilation equipment.
5.1.1 The hanging ducting should be flat, straight and tight.
5.1.2 The axis of the fan outlet should be kept on the same axis as the axis of the ventilation ducting.
5.1.3 In a tunnel with a large amount of water spray, the ducting should be installed with a water discharge nozzle as shown in the figure below (Figure 3) to release the accumulated water in time and minimize the additional resistance.
Figure 3 Schematic diagram of the tunnel ventilation duct water discharge nozzle
5.2 Avoid polluting the tunnel
The fan installation position should be at a certain distance (not less than 10 meters) from the tunnel entrance, and the influence of wind direction should be considered to avoid the polluted air from being sent into the tunnel again, resulting in circulating air flow and reducing the ventilation effect.
To be continued……
Post time: May-30-2022
