A fan a machine used to create flow within a fluid, typically a gas such as air. The fan contains a rotating arrangement of vanes or blades which address the fluid. The rotating assembly of rotor blades and hub is known as an impeller, a rotor, or a runner. Usually, it is included within some form of housing or case.This might direct the airflow or increase security by protecting against objects from contacting the fan cutting blades. Most fans are power by electric motors, but other sources of electric power may be used, including hydraulic motors and inner combustion engines.
Fans produce flows with high quantity and low pressure (although higher than ambient pressure), as opposed to air compressors which produce high pressures at a comparatively low volume. A fan blade will often rotate when subjected to a fluid stream, and devices that take good thing about this, such as anemometers and wind wind turbines, often times have designs similar to that of fan.
