DEVELOPMENT OF A LARGE-VOLUME SUPERCONDUCTING SOLENOID.
Abstract
Problems encountered in the development of largevolume superconducting solenoids have been investigated in the light of the experience induced by the realization of a particular prototype (8.0 inches in diameter, 4 ft long, 20 kilogauss at room temperature). The current-field characteristics of some useful superconducting materials (Nb, Mo-Re, Nb-Zr) have been measured; the results are discussed in terms of recent theories of superconductors. The spurious loss of the resistanceless state of a superconducting solenoid, which is particularly dangerous for large-volume devices, because of the large magnetic energy involved, was thoroughly investigated. Starting from the steady-state mechanisms of the quenching propagation in wire, the equations for current decay, voltage surge, wire-temperature rise, and energy transfer are derived; results of calculations for the prototype solenoid are presented. The design of the prototype solenoid, which can be divided somewhat arbitrarily into the magnetic-field generating system and the cryogenic system, is thoroughly detailed. The most important topics covered are: field calculation for multicoil solenoids (a machine program to calculate the field on- and off-axis is presented); magnetic stresses and magnetic energy; quenching process for multicoil solenoids; steady-state heat transfer caused by residual gas, thermal radiation and conduction (a derivation of the conduction loss with counterflow gas cooling is presented); and transient heat transfer, particularly during cooling down and quenching. Preliminary results are discussed, and suggestions for an improved design are made. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 16, 1964
- Accession Number
- AD0608445
Entities
People
- Lucien J. Donadieu
Organizations
- Massachusetts Institute of Technology