Electron Heat Conduction Coefficients at the Temperature Rise Phase and the Internal Disruption during the Sawtooth Oscillation of Tokamak

Abstract

The electron heat conduction coefficient χe inside the q=1 singular surface during the rise phase and the internal disruption of sawtooth oscillations were estimated from the experimental profiles, on the basis of an equation derived from the diffusion equation. The equation to estimate the central electron heat conduction coefficient χe(0) was obtained from theory and experiment as χe(0)=KrD2/t; rD the radius of q=1 surface and t the period of rise phase or internal disruption phase of sawtooth oscillation. The factor K is associated with their profiles in the rise phase and the internal disruption. It is suggested from a simulation of internal disruptions that the broadened profiles at the top of the sawtooth oscillation lead to the low values of χe.