Fans have the task of conveying air or other gaseous media, irrespective of their type or design.
The basic equipment package of each fan consists of an impeller and an electric motor that drives the impeller. The electric motor causes the impeller to rotate. The impeller in turn moves the air by drawing it in on the suction side of the system and blowing it out again on the pressure side.
The design of the fan influences both the direction from which the air is drawn in and blown out again (axial, radial, diagonal, tangential) as well as the system's design-related performance characteristics (e.g. volume flow, pressure, etc.).