Cryogenic techniques for large superconducting magnets in space

Conference · Thu Dec 01 04:00:00 EST 1988

OSTI ID:6184879

Green, M A

A large superconducting magnet is proposed for use in a particle astrophysics experiment, ASTROMAG, which is to be mounted on the United States Space Station. This experiment will have a two-coil superconducting magnet with coils which are 1.3 to 1.7 meters in diameter. The two-coil magnet will have zero net magnetic dipole moment. The field 15 meters from the magnet will approach earth's field in low earth orbit. The issue of high Tc superconductor will be discussed in the paper. The reasons for using conventional niobium-titanium superconductor cooled with superfluid helium will be presented. Since the purpose of the magnet is to do particle astrophysics, the superconducting coils must be located close to the charged particle detectors. The trade off between the particle physics possible and the cryogenic insulation around the coils is discussed. As a result, the ASTROMAG magnet coils will be operated outside of the superfluid helium storage tank. The fountain effect pumping system which will be used to cool the coil is described in the report. Two methods for extending the operating life of the superfluid helium dewar are discussed. These include: operation with a third shield cooled to 90 K with a sterling cycle cryocooler, and a hybrid cryogenic system where there are three hydrogen-cooled shields and cryostat support heat intercept points. Both of these methods will extend the ASTROMAG cryogenic operating life from 2 years to almost 4 years. 14 refs., 8 figs., 4 tabs.

• Research Organization: Lawrence Berkeley Lab., CA (USA)
• DOE Contract Number: AC03-76SF00098
• OSTI ID: 6184879
• Report Number(s): LBL-25735; CONF-8807123-2; ON: DE89013431
• Country of Publication: United States
• Language: English

Related Subjects

420201* -- Engineering-- Cryogenic Equipment & Devices
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ALLOYS
ASTROPHYSICS
CONTROL EQUIPMENT
COOLING
CRYOGENICS
CRYOSTATS
DESIGN
ELECTRICAL EQUIPMENT
ELECTROMAGNETS
EQUIPMENT
HELIUM DILUTION REFRIGERATION
MAGNETS
NIOBIUM ALLOYS
NIOBIUM BASE ALLOYS
PUMPING
REFRIGERATION
SHIELDING
SPACE VEHICLES
SUPERCONDUCTING DEVICES
SUPERCONDUCTING MAGNETS
SUPERFLUIDITY
THERMOSTATS
VEHICLES
YTTRIUM ALLOYS
YTTRIUM BASE ALLOYS