What Is The Main Function Of Tunnel Fan？

Tunnel fan is an abbreviation. As the name implies, it refers to the fan used in the tunnel. Tunnel fan is also called jet fan. Because the tunnel and the subway are tens of meters below the ground surface, it is not enough for the tunnel and the subway station to rely solely on the natural wind at the entrance and exit. It must install the tunnel fan to transport and regulate the air or remove the smoke and dust (smoke exhaust from the passing cars in the tunnel) for the needs of the staff and tourists. Tunnel fan (jet fan) is a special axial fan, which is mainly used in the longitudinal ventilation system of highway, railway and subway tunnels. Generally, it is hung on the top or both sides of the tunnel, does not occupy the traffic area, does not need to build another air channel, and the civil construction cost is low; the fan is easy to install, simple to operate and maintain, and is a very economic ventilation mode. When the tunnel fan (jet fan) is running, a part of the air in the tunnel is drawn from the end of the fan, accelerated by the impeller, and then shot out at a high speed from the other end of the fan. This part of high-speed air flow with high kinetic energy transmits the energy to other gases in the tunnel, and generates pressure rise to overcome the resistance of the tunnel, so as to promote the air flow in the tunnel along the direction of the fan jet air flow. When the flow velocity decays to a certain extent, the next group of fans will continue to work. In this way, fresh air is drawn from one end of the tunnel and dirty air is discharged from the other end