High-speed gas foil bearing turboalternator and turbocompressor for reverse brayton cryocooler

Abstract

A cryogenic turboalternator and turbocompressor that includes a magnet portion of an alternator that is positioned on a shaft in a way that improves overall cooling efficiency of the turboalternator and turbocompressor are presented. The magnet portion is on a shaft and is at or near an end of the shaft that is supported by journal bearings, which may be gas foil bearings. The magnet portion overhangs the journal bearings such that the magnet portion is not between the journal bearings. This relative positioning leads to improved cooling efficiency by having the bearings, which generate heat during operation, at decreased distances from the coldest portion of the turboalternator and turbocompressor, which can act as a heat sink. The resulting shortening of heat flow paths from bearings to heat sink may eliminate a need for circulating cooling fluid through the bearings, thereby improving thermal management and increasing operating efficiency.

Dependencies are inferred from the claim text.