Analysis and Design of a Gas-Lubricated, Sectored, Floating Ring Seal

Abstract

Helium buffered floating-ring seals used in cryogenic turbopumps are sujbect to large temperature variations, shaft centrifugal growth, and dynamic shaft excursions. To prevent dangerous contact friction over a wide range of operating conditions generally requires liberal clearances with consequent high leakage. Reduction of helium consumption translates into lower space vehicle helium storage requirements and thus increased payload. A hydrostatic sectored floating-ring seal is described with self-adjusting clearance capabilities that enables the seal to operate with small clearances over the operating range to minimize leakage.