Contrarotating Journal Bearings for Naval Propulsion Systems

Contrarotating propeller systems offer well-recognized advantages in propulsion efficiency. Unfortunately, circular bore journal bearings have no load capacity when used in contrarotation, but a quasi-squeeze effect may be induced by offset or preloaded sub arcs as these pass through the loaded region of the film. With this type of bearing, even when under steady load, the journal must orbit within the clearance space. The propagation of such orbits is described. The response is quantified by a Fourier analysis of the motion. Contrarotating journal bearings may be designed to support loads of the same general magnitude as conventional circular (non-rotating) bearings. Presented at the 46th Annual Meeting in Montreal, Quebec, Canada April 29-May 2, 1991