Accession Number:

ADA209875

Title:

Superconducting Meissner Effect Bearings for Cryogenic Turbomachines. Phase 1

Descriptive Note:

Final rept. Sep 1988-Mar 1989

Corporate Author:

CREARE INC HANOVER NH

Report Date:

1989-05-01

Pagination or Media Count:

52.0

Abstract:

State of the art miniature expansion turbines and centrifugal compressors used in spaceborne sensor cryocoolers employ self-acting gas bearings to achieve high reliability and long operating life. Because these bearings must run at room temperature to achieve adequate stiffness and stability, they result in an avoidable source of heat leak to the process gas, thereby lowering overall cycle efficiency and increasing the system launch weight. This report shows that the gas bearings can be replaced by Meissner effect bearings fabricated from high temperature superconducting materials. Analyses are presented to predict Meissner bearing performance, and a preliminary design of a miniature expansion incorporating Meissner bearings is conceptualized. Because these bearings operate at a cryogenic temperatures, a substantial reduction in heat leak to the process gas can be achieved. For a typical cryocooler providing 1 watt of cooling at 10 K, a 40 reduction in input cycle power can be achieved by replacing the self-acting gas bearings by Meissner bearings in the cold expansion turbine.

Subject Categories:

  • Hydraulic and Pneumatic Equipment
  • Machinery and Tools
  • Electricity and Magnetism

Distribution Statement:

APPROVED FOR PUBLIC RELEASE