Centrifugal Fan and Blower

What Is a Centrifugal Fan and How Does It Work?

A centrifugal fan is a mechanical device designed to move air or gas using centrifugal force. Any equipment that generates airflow can be categorized as a fan. Typically, it consists of a rotating impeller that produces the airflow and a stationary casing that directs the flow into and out of the impeller. The shapes of both the impeller and casing can vary significantly depending on the application.

Fans are commonly classified based on the type of airflow through the impeller blades. These classifications include axial flow, radial flow, mixed flow, and cross flow. Many fan types derive their names directly from these flow characteristics, while others are named according to additional functional or structural properties.

Centrifugal fans use radial-flow impellers, where air enters the casing axially and exits tangentially. The casing is typically a volute or scroll-type design. A substantial portion of the energy transferred to the air is generated by centrifugal force, which is why this type is called a centrifugal fan.

The pressure-generating capability of radial-flow fans depends on several factors, including the blade depth, tip speed, and blade angle — all of which directly influence the performance and efficiency of the fan in industrial ventilation and air handling systems.