A centrifugal fan or centrifugal blower is a pump or motor that moves air. It pulls the air inside the blower and then pushes it out at a 90º angle. The two main components of a centrifugal fan are the motor and the impeller. An impeller sucks or pulls air, in contrast to a propeller which pushes air.
Some fans can pull and push air at lower than a 90º angle; these fans are called mixed flow fans.
Centrifugal fans can either have no exterior housing or structure to offer protection or they can be built with some protective housing.
Our types of centrifugal fans are mainly made of forward curved blades. Attached vedio for your understanding.