Divertor transport study in the large helical device

JOURNAL OF NUCLEAR MATERIALS

卷:363

Article; Proceedings Paper

Kobayashi, M. ; Feng, Y. ; Masuzaki, S. ; Shoji, M. ; Miyazawa, J. ; Morisaki, T. ; Ohyabu, N. ; Ashikawa, N. ; Komori, A. ; Motojima, O. ; Igitkhanov, Y. ; Sardei, F. ; Reiter, D.

关键词: LHD;    3D edge plasma;    edge modelling;    stochastic boundary;   

DOI  :  10.1016/j.jnucmat.2007.01.038

来源: Elsevier

【 摘 要 】

The edge transport properties in LHD have been investigated in order to clarify divertor/SOL functions of heliotron type device. The momentum loss, mainly through friction of counter-flows induced by ergodic field lines, breaks the pressure conservation along flux tubes. This prevents high recycling regime even at high density operation, (n) over bar similar to 7 x 10(19) m(-3). The momentum loss is found to be larger than in W7-AS. This is because of the higher ratio of perpendicular and parallel transport scale length, similar to 10(-4), in the ergodic layer, which enhances the friction between counter-flows more than in the island divertor. In the heliotron configuration, a large temperature drop from LCFS to divertor by an order of magnitude is easily realized due to the long connection length in the ergodic layer. This is certainly a favourable feature for future reactors in terms of reduction of damage on the divertor plate. (c) 2007 Elsevier B.V. All rights reserved.

【 授权许可】

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