Fan is dependent on the input of mechanical energy, increase the pressure of gas and send gas machinery, it is a driven fluid machinery. Fan is China’s customary abbreviation for gas compression and gas transmission machinery, usually said that the fan includes fan, blower, wind turbine.
Fan widely used in factories, mines, tunnels, cooling towers, vehicles, ships and buildings of ventilation, dust and cooling, boiler and industrial furnace ventilation and induced draft; Cooling and ventilation in air-conditioning equipment and household electrical appliances; drying and selection of grain; inflating and propulsion of wind tunnels and hovercraft.
Classification and use of fans
Classify by the direction of airflow
A. The centrifugal fan-the axial flow is compressed under the action of centrifugal force after entering the impeller of the fan, and mainly flows along the radial direction.
B. Axial flow fan-air flow enters the rotating blade channel axially. Because of the interaction between the blade and the gas, the gas is compressed and flows approximately along the axis direction on the cylindrical surface.
C. Mixed flow fan-gas and the main shaft into the direction of a certain angle rotating blade, approximately along the conical flow.
D. Cross-flow fan-gas across the rotating blade, and by the role of increased pressure blade.
According to the principle of action
A. Turbine fan — a fan that conveys gas by compressing it with rotating blades.
B. Positive displacement fan-a machine that compresses and conveys gas by changing the volume of the gas.
