Scrape-off layer power flux measurements in the Tore Supra tokamak

被引:27
作者
Gunn, J. P. [1 ]
Dejarnac, R. [2 ]
Devynck, P. [1 ]
Fedorczak, N. [3 ]
Fuchs, V. [2 ]
Gil, C. [1 ]
Kocan, M. [4 ]
Komm, M. [2 ]
Kubic, M. [1 ]
Lunt, T. [4 ]
Monier-Garbet, P. [1 ]
Pascal, J. -Y. [1 ]
St Laurent, F. [1 ]
机构
[1] CEA, IRFM, F-13108 St Paul Les Durance, France
[2] Assoc EURATOM IPP, Prague 18200 8, Czech Republic
[3] Univ Calif San Diego, Ctr Momentum Transport & Flow Org, San Diego, CA 92093 USA
[4] EURATOM, Max Planck Inst Plasmaphys, D-85748 Garching, Germany
关键词
ION COLLECTION; PROBES;
D O I
10.1016/j.jnucmat.2013.01.055
中图分类号
T [工业技术];
学科分类号
08 ;
摘要
A new method to measure power flux in strongly magnetized plasmas is described, while the flaws inherent in standard Langmuir probe techniques are demonstrated. Instead of small cylindrical pins which overestimate the ion current density by several 100%, a concave probe has been developed which is immune to sheath expansion, and which inherently provides accurate measurements. A retarding field analyzer directly measures the ion component of the power flux by means of an integral method that eliminates the need to calculate the heat transmission factor. Evidence shows that strong secondary electron emission from surfaces with non-oblique magnetic field incidence angles is ubiquitous in the scrape-off layer of the Tore Supra tokamak. This results in sheath collapse, causing the power flux to be dominated by the electrons. The radially integrated power flux measured by the probes agrees well with the power convected to the limiter. (C) 2013 Elsevier B. V. All rights reserved.
引用
收藏
页码:S184 / S188
页数:5
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