Quenching dynamic process and protection by shunt resistors of solenoid superconducting magnets with graded current density

Using graded current density in the design of multilayer-solenoid superconducting magnets is an effective way to save on the total weight of superconducting materials. Following a discussion of the relationship between quench propagation velocity and the geometrical location of the windings involved, the authors propose a mathematical model applicable to both magnets with graded current density and to magnets protected by multishunt resistors. Several numerical examples were calculated using a computer program based on this model. The selection of shunt resistors for protecting the superconducting magnet is also discussed.