The scroll wrap is the main movement part of compressor, only have the tooth, have no abrasion, thus the life is longer, so this is free maintenance compressor.

Well, when the aluminum spool is rotating, the closeness of the aluminum to the magnets creates what's called an "eddy current," and this eddy current creates the braking effect on the spool.

The nonuniform distribution of induced velocity on the rotor disk which is derived from the wang's generalized fix vortex theory is taken into account.