NORMAL ZONE EVOLUTION AND PROPAGATION IN A CRYOGENICALLY STABLE SUPERCONDUCTOR.

Abstract

The time evolution of a normal zone and propagation of the normal front are calculated for a cryogenically stable superconductor resembling the configuration of a UW Energy Storage Conductor laboratory prototype of 13. 5 cm diameter stabilized with 400 RRR A1 carrying 765 kA in a field of 3. 5 T. The coupled heat transport and current diffusion equations with temperature dependent physical properties are solved numerically. Both radial adiabatic and superfluid helium cooling cases are treated. A factor of four enhancement in the propagation velocity occurs in the adiabatic case and a transient propagation velocity in the superfluid helium cooling case exists because of the heat generation due to the transient non-uniform current distribution in the stabilizer.