IAEA Fusion Energy Conference 2010

Proceedings of the 23rd IAEA Fusion Energy Conference
Daejeon, 11-16 October 2010

Organized by the International Atomic Energy Agency
and hosted by the Government of the Republic of Korea


(THS/P3-02) Integrated Simulation of ELM Triggered by Pellet through Energy Absorption and Transport Enhancement

N. Hayashi1), V. Parail2), F. Koechl3), N. Aiba1), T. Takizuka1), S. Wiesen4), P.T. Lang5), N. Oyama1), T. Ozeki1)
1) Japan Atomic Energy Agency, Naka, Ibaraki-ken 311-0193, Japan
2) EURATOM/CCFE Fusion Association, Culham Science Centre, Abingdon OX14 3DB, UK
3) Association EURATOM-ÖAW/ATI, Atominstitut, TU Wien, 1020 Vienna Austria
4) EURATOM Association Forschungszentrum Jülich GmbH, Institute for Energy Research, IEF-4, Plasmaphysics, D-52425 Jülich, Germany
5) Max-Planck-Institut fur Plasmaphysik, EURATOM Association, Boltzmannstrasse 2, 85748 Garching, Germany

Abstract.  Two integrated core / scrape-off-layer (SOL) / divertor transport codes TOPICS-IB and JINTRAC with links to MHD stability codes have been coupled with models of pellet injection to clarify effects of pellet on the ELM behavior. The energy absorption and the transport enhancement by the pellet were found to trigger the ELM. The ablated cloud of pellet absorbs the background plasma energy and causes the radial redistribution of pressure due to the subsequent E×B drift. On the other hand, the sharp increase in local density and temperature gradients in the vicinity of ablated cloud causes the transient enhancement of heat and particle transport. Both mechanisms produce a region of an increased pressure gradient in the background plasma profile within the pedestal, which triggers the ELM. The mechanisms can explain a wide range of experimental observations.

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