Quench propagation in the SSC dipole magnets

The effects of quench propagation are modeled in 40-mm- and 50-mm-diameter collider dipole magnet designs. A comparative study of the cold diode (passive) and quench heater (active) protection schemes is presented. The SSCQ modeling program accurately simulates the axial quench velocity and uses phenomenological time delays for turn-to-turn transverse propagation. The axial quench velocity is field dependent and, consequently, each conductor's quench profile is tracked separately. No symmetry constraints are employed, and the distribution of the temperatures along the conductor differs from the adiabatic approximation. A single magnet has a wide margin of self-protection, which suggests that passive protection schemes must be considered.