Jet fan is a kind of fan used in tunnels. Because its scale is used for water conservancy DAMS, railways, subways, roads and other places of the tunnel, so its transport of air volume must be uniform. When the jet fan used to transport the material reaches a certain position, the air volume will be greatly reduced. Why is that?

(1) When the air duct of the jet fan is placed in the tunnel, it may be because it is not placed regularly, or the air duct leaks and breaks, resulting in the decrease of air volume.

(2) In the escort process, the jet fan passes through the air duct, air duct, etc., and the elastic barrier of the air duct is asymmetric, which plays a great role in hindering the cyclone. Gas measurements and density are also factors in the barrier size of wind trekking.

(3) Rotating axial flow fans are usually used for jet fans and adopt the type of double generators. In this case, the fan pressure exposure should be much higher than the single-engine motor. After the fan starts, the stability of the external voltage meets the speed of the generator, and the fan care increases or decreases.