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Abstract

The shapes of the density profiles of electron, hydrogen isotopes and impurities in the core of tokamak plasmas have important consequences on both the overall plasma stability as well as on the plasma performance. The theoretical understanding of the experimentally observed transport behaviours of electrons and impurities is therefore an important and active field of research in physics of tokamak plasmas. In many conditions, it is observed that particle and impurity transport is produced by non-collisional (anomalous) effects. In this paper we assume that the same instabilities that are thought to be responsible for anomalous core heat losses, are also responsible for anomalous particle transport. We investigate the particle and impurity transport produced by ion temperature gradient (ITG) and trapped electron modes (TEM), considering realistic values of plasma parameters obtained in large tokamak experiments like the Axial Symmetric Divertor Experiment (ASDEX) -Upgrade (AUG) and the Joint European Torus (JET). Transport modelling of anomalous heat transport is often described by means of theoretical models based on quasi{linear (QL) fluid theory. These models compute the transport produced by the most unstable linear modes. While this simplified description can be considered adequate to some extent to describe the heat transport, we show here that this can be largely inadequate to describe particle transport. As it is shown in Fig. 1, there are conditions for which the direction of the particle transport, determined by the sign of the phase shift between density and electrostatic potential fluctuations, is found to depend on the magnitude of the poloidal wave number. QL approaches must be based on values of the poloidal wave number which are close to those where the non{linear (NL) transport is maximum to obtain the particle flux in the same direction (inward or outward) as it is obtained in NL simulations.

Additional information

Authors: GIROUD C, EURATOM-UKAEA Fusion Association, Culham Science Centre, Abingdon (GB);MCDONALD D C, EURATOM-UKAEA Fusion Association, Culham Science Centre, Abingdon (GB);ZASTROW K-D, EURATOM-UKAEA Fusion Association, Culham Science Centre, Abingdon (GB);PUIATTI M E, Associazione Euratom-ENEA sulla Fusione, Consorzio RFX, Padova (IT);VALISA M, Associazione Euratom-ENEA sulla Fusione, Consorzio RFX, Padova (IT);ANGIONI C, Max-Planck-Institut für Plasmaphysik, IPP-EURATOM Association, Garching (DE);DANNERT T, Max-Planck-Institut für Plasmaphysik, IPP-EURATOM Association, Garching (DE);DUX R, Max-Planck-Institut für Plasmaphysik, IPP-EURATOM Association, Garching (DE);JENKO F, Max-Planck-Institut für Plasmaphysik, IPP-EURATOM Association, Garching (DE);MAGGI C F, Max-Planck-Institut für Plasmaphysik, IPP-EURATOM Association, Garching (DE);PEETERS A G, Max-Planck-Institut für Plasmaphysik, IPP-EURATOM Association, Garching (DE);MASLOV M, Centre de Recherches en Physique des Plasmas, Association EURATOM-Confédération Suisse, Ecole Polytechnique Fédérale de Lausanne (CH);WEISEN H, Centre de Recherches en Physique des Plasmas, Association EURATOM-Confédération Suisse, Ecole Polytechnique Fédérale de Lausanne (CH);ZABOLOTSKY A, Centre de Recherches en Physique des Plasmas, Association EURATOM-Confédération Suisse, Ecole Polytechnique Fédérale de Lausanne (CH);MAZON D, Département de Recherches sur la Fusion Contrôlée, Association Euratom-CEA sur la Fusion, CEA Cadarache, Saint-Paul-lez-Durance (FR)
Bibliographic Reference: An oral paper given at: 32nd EPS Conference on Controlled Fusion and Plasma Physics Organised by: Asociación EURATOM-CIEMAT para Fusión Held at: Congress Palace of Tarragona, Tarragona (ES)
Availability: Available from Association EURATOM-CEA, Departement de Recherches sur la Fusion Controlee, CEA Cadarache, F-13108 St Paul-Lez-Durance, FranceL%Tel: (+33) 4 42 25 70 01; Fax: (+33) 4 42 25 64 21 E-mail: dirdrfc@drfc.cad.cea.fr
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