Design and fabrication of the cryostat for the floating coil of the Levitated Dipole Experiment (LDX)

Citation
A. Zhukovsky et al., Design and fabrication of the cryostat for the floating coil of the Levitated Dipole Experiment (LDX), IEEE APPL S, 10(1), 2000, pp. 1522-1525
Citations number
6
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science
Journal title
IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY
ISSN journal
1051-8223 → ACNP
Volume
10
Issue
1
Year of publication
2000
Pages
1522 - 1525
Database
ISI
SICI code
1051-8223(200003)10:1<1522:DAFOTC>2.0.ZU;2-H
Abstract
The Levitated Dipole Experiment (LDX) is a new, innovative magnetic confine ment fusion experiment being designed and installed in collaboration with C olumbia University at the Massachusetts Institute of Technology (MIT). The primary objective of the experiment is to investigate the possibility of st eady-state, high-beta plasma confinement with near classical transport. The main component of the experiment is a levitated cryostat with a 5.7 T Nb3S n superconducting magnet, housed in an Inconel high pressure helium vessel. The pressure vessel is surrounded by a large thermal mass radiation shield and an outer vacuum shell, all of which are magnetically levitated inside a much larger vacuum chamber. The cryostat, now under construction, is desc ribed in this paper. The cryostat keeps the magnet temperature between 5 an d 10 K during 8 hours of levitated operation. A low heat leak support syste m for the helium vessel and the shield is designed to withstand impact forc es of 10 g in case of a levitating failure. The helium vessel is filled to 125 atm at room temperature with 1.4 kg of helium. The helium vessel and th e shield are equipped with a tube heat exchanger for initial nitrogen magne t cooling and daily helium re-cool from a high of 20-25 K back down to 5K. This cooling system uses hermetically sealed, retractable cryogenic transfe r lines when the cryostat is resting in the bottom charging station of the LDX vacuum chamber. The magnet is charged and discharged inductively by an outer charging magnet.