Semi analytical study of ironless permanent magnet devices being both a coupling and an axial bearing for naval propulsion

In this paper, two kinds of cylindrical air gap devices are studied. These devices consists of parallelepipedical magnets stuck in ironless cores, the first one is the classical structure of PM coupling where alternated (north and south) magnets with radial magnetizations are used. The second one is an original structure of PM coupling where two rings of magnets with axial magnetizations are stacked.