Quenching in epoxy-impregnated superconducting solenoids: Prediction and verification

An experimentally verified model that predicts quenching characteristics of a multi-section, epoxy-impregnated superconducting solenoid is described. The model uses a semi-empirical relationship to correlate the turn-to-turn normal zone growth to the propagation along a single wire. Normal zone growth in a solenoid is modeled assuming that transverse propagation is dominant. The computer predictions are compared with experimental results from small multi-section solenoids. The coil currents and terminal voltages predicted by this model agree with the experiments at high currents. However, at low currents the agreement is less satisfactory. The reasons for the dissagreement are understood and explained.