Total friction area contacted by the pads during one revolution of the rotor.

Area over which a hinged door travels during a cycle.

the area of the circle delineated by the wind generator's rotating blades.

The area swept by the turbine rotor, A = π R 2 , where R is the radius of the rotor.

see area swept.

In reference to a wind energy conversion device, the area through which the rotor blades spin, as seen when directly facing the center of the rotor blades.