DC centrifugal fans are mechanical devices that use rotating impellers to draw kinetic energy and push out air or gas in a particular direction. The housing or enclosure of the fan helps maintain the direction of the outgoing stream of air or gas. The kinetic energy of the rotating impellers increases the speed and volume of the outgoing stream of air or gas. These fans are also known as centrifugal blowers. The feature that distinguishes them from axial fans is the pressure ratio. When we say DC or direct current, the flow of electric current is unidirectional, unlike AC fans.