Community Research and Development Information Service - CORDIS

  • European Commission
  • CORDIS
  • Publications
  • Characterization of pedestal parameters and edge localized mode energy losses in the Joint European Torus and predictions for the International Thermonuclear Experimental Reactor

Abstract

This paper presents the experimental characterization of pedestal parameters, edge localized mode (ELM) energy, and particle losses from the main plasma and the corresponding ELM energy fluxes on plasma facing components for a series of dedicated experiments in the Joint European Torus (JET). From these experiments, it is demonstrated that the simple hypothesis relating the peeling-ballooning linear instability to ELM energy losses is not valid. Contrary to previous observations at lower triangularities, small energy losses at low collisionality have been obtained in regimes at high plasma triangularity and q95~4.5, indicating that the edge plasma magnetohydrodynamic stability is linked with the transport mechanisms that lead to the loss of energy by conduction during type I ELMs. Measurements of the ELM energy fluxes on the divertor target show that their time scale is linked to the ion transport along the field and the formation of a high energy sheath, in agreement with kinetic modeling of ELMs. Higher density ELMs, of a convective nature, lead to overall much longer time scales for the ELM energy flux, with more than 80% of the ELM energy flux arriving after the surface divertor temperature has reached its maximum value. On the contrary, for low density ELMs, of a conductive nature, up to 40% of the energy flux arrives at the divertor target before the surface divertor temperature has reached its maximum value. These large and more conductive ELMs may lead to up to ~50% of the ELM energy reaching the main wall plasma facing components instead of the divertor target. The extrapolation to the International Thermonuclear Experimental Reactor of the obtained results is described and the main uncertainties discussed.

Additional information

Authors: LOARTE A, EFDA Close Support Unit, Garching (DE);SAIBENE G, EFDA Close Support Unit, Garching (DE);SARTORI R, EFDA Close Support Unit, Garching (DE);KEMPENAARS M, FOM Instituut voor Plasmafyisica Rijnhuizen, Euratom-FOM Association, Trilateral Euregio Cluster, Nieuwegein (NL);BEURSKENS M, FOM Instituut voor Plasmafyisica Rijnhuizen, Euratom-FOM Association, Trilateral Euregio Cluster, Nieuwegein (NL);DE BAAR M, FOM Instituut voor Plasmafyisica Rijnhuizen, Euratom-FOM Association, Trilateral Euregio Cluster, Nieuwegein (NL);LOMAS P J, EURATOM-UKAEA Fusion Association, Culham Science Centre, Abingdon (GB);MATTHEWS G, EURATOM-UKAEA Fusion Association, Culham Science Centre, Abingdon (GB);FUNDAMENSKI W, EURATOM-UKAEA Fusion Association, Culham Science Centre, Abingdon (GB);PARAIL V, EURATOM-UKAEA Fusion Association, Culham Science Centre, Abingdon (GB);GONCALVES B, Associacao EURATOM-IST, Centro de Fus?o Nuclear, Instituto Superior Tecnico, Lisbon (PT);CORRE Y, Association EURATOM-VR, KTH Royal Institute of Technology, Stockholm (SE);EICH T, Max-Planck-Institut für Plasmaphysik, IPP-EURATOM Association, Garching (DE);KALLENBACH A, Max-Planck-Institut für Plasmaphysik, IPP-EURATOM Association, Garching (DE);SUTTROP W, Max-Planck-Institut für Plasmaphysik, IPP-EURATOM Association, Garching (DE);LÖNNROTH J, Association EURATOM-TEKES, Helsinki University of Technology (FI);BECOULET M, Département de Recherches sur la Fusion Contrôlée, Association Euratom-CEA sur la Fusion, CEA Cadarache, Saint-Paul-lez-Durance (FR);MONIER-GARBET P, Département de Recherches sur la Fusion Contrôlée, Association Euratom-CEA sur la Fusion, CEA Cadarache, Saint-Paul-lez-Durance (FR);DE LA LUNA E, Asociaco´n EURATOM-CIEMAT para Fusion,Madrid (ES);GONÇALVES B, Associacao EURATOM-IST, Centro de Fusão Nuclear, Instituto Superior Técnico, Lisbon (PT);SILVA C, Associacao EURATOM-IST, Centro de Fusão Nuclear, Instituto Superior Técnico, Lisbon (PT)
Bibliographic Reference: An article published in: Physics of Plasmas Volume 11, Number 5 May 2004
Availability: This article can be accessed online by subscribers, and can be ordered online by non-subscribers, at: http://scitation.aip.org/pop/
Follow us on: RSS Facebook Twitter YouTube Managed by the EU Publications Office Top