[Table of Contents]

Plasma and Fusion Research

Volume 8, 2402126 (2013)

Regular Articles

Comparison of Observed Divertor Heat Flux and Modeling Results at LHD
Peter DREWELOW, Suguru MASUZAKI1), Sergey BOZHENKOV, Yuehe FENG, Marcin W. JAKUBOWSKI, Yasuhiro SUZUKI1), Robert WOLF, Hiroshi YAMADA1) and LHD Experiment Group
Max-Planck-Institut für Plasmaphysik, EURATOM Assoziation, 17491 Greifswald, Germany
1)
National Institute for Fusion Science, Toki 509-5292, Japan
(Received 22 November 2012 / Accepted 26 June 2013 / Published 15 November 2013)

Abstract

The divertor strike line pattern on the helical divertor of LHD was observed with an infra red camera. The derived heat flux pattern show multiple distinct strike lines depending on the equilibrium magnetic configuration. Predictions of such divertor heat loads thus require a modeling of the magnetic configuration and the heat transport in the magnetic edge. Equilibrium magnetic topologies were analyzed with HINT2, while the plasma fluid model code EMC3 was used to simulate the energy transport in the edge. The measured multi peak structure of the divertor heat flux is correlated to the intersection points of elongated loop shaped flux tubes of long LC field lines. But the fluid model could not recreate the total energy load and the multiple heat flux peaks on the divertor. A Variation in the plasma density ne as a transport parameter in order to fit the simulated heat flux to the measured one shows a contradicting tendency.

Keywords

LHD, helical divertor, strike line pattern, finite beta, stochastic field lines, HINT2, EMC3

DOI: 10.1585/pfr.8.2402126

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This paper may be cited as follows:

Peter DREWELOW, Suguru MASUZAKI, Sergey BOZHENKOV, Yuehe FENG, Marcin W. JAKUBOWSKI, Yasuhiro SUZUKI, Robert WOLF, Hiroshi YAMADA and LHD Experiment Group, Plasma Fusion Res. 8, 2402126 (2013).