Centrifugal fan (English: centrifugal fan) is a mechanical device for moving air or other gases at an angle relative to the direction of the incoming fluid. Centrifugal fans often have ducts to direct air out in a specific direction or through radiators, then centrifugal fans are also known as blowers (blowers) or squirrel cage fans ( squirrel -cage fan) (because it's like a wheel for a hamster to run). This type of centrifugal fan increases the speed and volume of the air flow thanks to the rotating blades.