Tokamak Heat Transport Due to Tearing Modes

Abstract

Magnetic field perturbations accompanying the tearing instability allow rapid heat transport across regions enclosing mode-rational equilibrium flux surfaces. The electron-energy transport equation for this process is derived, under the assumptions of cylindrical geometry, incompressible flow, and relatively weak density gradients. For the thermoelectric instability predicted by kinetic theory, a quasilinear description of local flattening of the temperatures profile is obtained. The self-consistent field perturbation is shown to be quite weak, $\frac{\delta B}{B_0}\sim {10}^{-4\mathrm{}}$; yet it yields a localized heat flux far exceeding pseudoclassical estimates.