Design and development of bump-type gas foil journal bearings for cryogenic turboexpander

Abstract

A cryogenic turboexpander is also referred as rotatory expansion device used in gas processing and cryogenic liquefaction. The operational objective of cryogenic turboexpander is to refrigerate a gas stream, by expanding the process gas in an expansion turbine. A mid-sized cryogenic turboexpander rotates at very high speed for better aerodynamic efficiency. The need for high rotational speed and contamination free operation brings constraints on the selection of appropriate bearings for the turboexpander. Gas bearings is a solution for above requirement. Present work describes on design and development and performance study of bump-type gas foil journal bearing(GFJB) for a turboexpander with 16 mm rotor diameter rotating at 80,000 rpm.