TORQUE ON A SUPERCONDUCTING TOROID IN A UNIFORM FIELD.
Abstract
The torques on superconducting lead toroids immersed in various uniform fields were measured and calculated as a function of angular position. The calculations, based on ideal superconducting behavior, agree with experiment for the closed torus, if persistent current decrease due to critical surface fields is considered. The recognition of trapped-flux phenomena is needed to explain the measured results for the open torus, when it has been cooled in a nonzero field or when a magnetic transition to superconductivity has been made. The analytical model used magnetic moments for a torus in an axial field and in a perpendicular field, rigorously calculated elsewhere. These methods of obtaining approximations to the moments presented may possibly apply to more general toroidal bodies. The total magnetic moment (and thus the torque) for arbitrary angular position is found by superposition, a result not previously obtained. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 05, 1967
- Accession Number
- AD0664207
Entities
People
- B. J. Wilson
- E. E. King
- J. R. Miller
Organizations
- United States Naval Research Laboratory