Cryogenic stability of composite conductors taking into account transient heat transfer

To predict stability behaviour of various conductors under different cooling conditions, a computer program was developed to solve the one-dimensional heat diffusion equation along the conductor using temperature dependent material parameters. Transient heat transfer is included basing on results of earlier heat transfer measurements. To check the validity of these calculations experiments were performed using a copper stabilized multifilamentary NbTi-superconductor under pool boiling conditions. The normal transition was initiated by an ohmic heater. The minimum energy needed to induce quenching as well as the propagation velocity of the normal zone are then compared with numerical results and show good agreement.