Takahide Nakayama

Quench simulation analysis of a superconducting coil

Abstract A quench simulation program has been developed with the intention of identifying a quench position in a superconducting coil and it has been applied to behaviour analysis of an artificially quenched superconducting coil. The superconducting coil is a solenoidal, bobbinless, and densely wound impregnated coil with many voltage terminals, thermocouples and heaters. The propagation of a normal zone was made two-dimensional by a one-turn-heater or three-dimensional by a point-heater set in the coil. The time-spatial changes in terminal voltages and temperatures agree well with those obtained from the simulation analysis within an accuracy of ± 10 ms or ± 1 mm. If accurate thermal properties of the materials constituting the superconducting coil are obtained, identification of the quench position in the coil should be possible. Normal front velocities and effective thermal conductivities of the radial, azimuthal and axial directions are also analysed from experimental results.