A computer program was developed to model the effects of normal region propagation in the longitudinal direction (along the conductor) and in the two transverse directions in a superconducting coil in a multicoil system. A simulation of 3D quench propagation in real space was done using a logical coordinate system in which each magnet is transformed into a single long conductor which is divided into finite-length elements. Since an element can be associated with geometry-related information such as the element length, the local magnetic field influence coefficients, and the relationship to adjacent elements in 3D, the quench propagation in any type of 3D configuration can be simplified to a 1D problem. As the growth of the normal region is determined, the transient current decay is calculated based on increases in conductor temperature and resistance. This calculation can be done for multiple, inductively coupled systems through the use of a circuit analysis subroutine. We describe the code logic and give results for calculated versus measured quench times in a single coil system.
