Full featured implementation of quench simulation in superconducting magnets

Abstract

Professional software is presented for superconducting quench simulation, applicable to magnets with a single or multiple coils, with or without iron, operating in either the persistent mode or from external power. Drift, dump and charge simulations are also possible. The method assumes that a quench starts at an arbitrary point of a coil and propagates in three dimensions longitudinally along the conductors and transversely across the insulation. Multiple independent fronts can coexist in any or all of the coils. Local magnetic fields and coil inductive couplings are calculated by a finite element method. The circuit equations are solved by a time difference method. All material properties are temperature dependent, and local fields, temperatures, front velocities, coil currents, terminal voltages and turn-to-turn voltages are all obtained by solving the corresponding equations at each point and time. Quench protection systems are automatically simulated. We present an application for a 4T, 1 m bore, fully iron shielded MRI magnet built by TAC, and a comparison with actual measurements in a test coil.