Criteria for the numerical convergence of quench simulations in CICC’S

Quench initiation and evolution in force-flow cooled conductors is a non-linear phenomenon that leads to a thermal runaway from a metastable situation. Because of the high degree of non-linearity associated with the expulsion of the helium coolant and the change of material properties in the wide range of temperature spanned, the analysis of quench mostly resorts on numerical simulation. In this paper, we show that there are specific situations in which the numerical analysis has problems in reaching convergence. The result is a large overestimation of critical parameters such as normal zone propagation velocity and maximum pressure. Based on established results, we give criteria for the selection of suitable space and time steps to obtain numerically converged and physically sound results.