L-mode and inter-ELM divertor particle and heat flux width scaling on MAST

[摘要] The distribution of particles and power to plasma-facing components is of key importance in the design of next-generation fusion devices. Power and particle decay lengths have been measured in a number of MAST L-mode and H-mode discharges in order to determine their parametric dependencies, by fitting power and particle flux profiles measured by divertor Langmuir probes, to a convolution of an exponential decay and a Gaussian function. In all discharges analysed, it is found that exponential decay lengths mapped to the midplane are mostly dependent on separatrix electron density (n(e,sep)(0.65 +/- 0.15) L-mode, (n(e,sep)(0.76 +/- 0.19) H-mode) and plasma current I-p(-0.36 +/- 0.11) L-mode, I-p(-1.05 +/- 0.18) H-mode) (or parallel connection length). The widths of the convolved Gaussian functions have been used to derive an approximate diffusion coefficient, which is found to vary from 1 m(2)/s to 7 m(2)/s, and is systematically lower in H-mode compared with L-mode. Crown Copyright (C) 2013 Published by Elsevier B.V. All rights reserved.

[发布日期] 2013-07-01

[效力级别]  Proceedings Paper