The greater the pressure of the centrifugal fan, the faster the motor rotates and the greater the current; on the contrary, the lower the pressure of the centrifugal fan, the slower the motor rotates and the smaller the current.

The centrifugal fan is a machine that relies on the input mechanical energy to increase the gas pressure and discharge the gas. It is a driven fluid machine. Centrifugal fans are widely used in ventilation, dust removal and cooling of factories, mines, tunnels, cooling towers, vehicles, ships and buildings; ventilation and induction of boilers and industrial furnaces; cooling and cooling of air conditioning equipment and household appliances Ventilation; drying and selection of grain; wind tunnel wind source and inflation and propulsion of hovercraft, etc.

Working principle of centrifugal fan:

The working principle of the centrifugal fan is basically the same as that of the turbo compressor, but because the gas flow rate is low and the pressure changes little, it is generally not necessary to consider the change of the gas specific volume, that is, the gas is treated as an incompressible fluid.

The centrifugal fan is based on the principle of converting kinetic energy into potential energy, using the high-speed rotating impeller to accelerate the gas, then decelerate, change the flow direction, and convert kinetic energy into potential energy (pressure). In a single-stage centrifugal fan, the gas enters the impeller from the axial direction, the gas changes to the radial direction as it flows through the impeller, and then enters the diffuser.

In a diffuser, the gas changes direction of flow causing a deceleration, which converts kinetic energy into pressure energy. The increase in pressure occurs mainly in the impeller and secondarily in the diffusion process. In a multi-stage centrifugal fan, a recirculator is used to direct the airflow to the next impeller, creating higher pressure.