Design and test of a wet type helium turbo-expander with an alternator as a brake

Conference · Sat Dec 31 04:00:00 EST 1994

OSTI ID:45489

Kato, T; Miyake, A; Kawano, K; Hamada, K; Hiyama, T; Iwamoto, S; Ebisu, H; Tsuji, H ^[1]; Saji, N; Kaneko, Y ^[2]

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1. Japan Atomic Energy Research Institute, Ibaraki-ken (Japan)
2. Ishikawajima-Harima Heavy Industries Co. Ltd., Tokyo (Japan); and others

A wet type helium turbo-expander with expected adiabatic efficiency of 70% at inlet pressure, temperature, and outlet pressure of 1.3 MPa, 6.0 K, and 0.2 MPa, respectively, has been developed. An alternator is adopted as a brake where a permanent magnet is held in the turbine shaft. And a self-acting gas bearing is used at thrust and journal bearings. An electromagnet supports thrust bearing to lift up the thrust disk when initiating operation. Design mass flow rate of the turbine is determined to be 60 g/s, corresponding to the JT mass flow rate in the existing helium liquefier/refrigerator. In the cryogenic performance test, the turbine had increased helium liquefaction rate by four times larger than the liquefaction rate without turbine operation.

• OSTI ID: 45489
• Report Number(s): CONF-930703--
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
70 PLASMA PHYSICS AND FUSION TECHNOLOGY
DESIGN
HELIUM
PERFORMANCE TESTING
REFRIGERATORS
TURBOMACHINERY