H-mode Snowflake Divertor Plasmas on TCV

POSTER

Abstract

An ELMy H-mode ``snowflake'' divertor is established and studied for the first time in the TCV tokamak. The H-mode access and the ELM dynamics is compared to a conventional single-null diverted configuration. The snowflake configuration exhibits $15\%$ higher confinement and 2 to 3 times lower ELM frequency. Ideal MHD stability analysis suggests enhanced stability of the snowflake H-mode pedestal to mid- to high-toroidal-mode-number modes. The capability of the snowflake to redistribute the edge power on the additional strike points has been confirmed experimentally.

Authors

  • Francesco Piras

    • CRPP/EPFL

  • Stefano Coda

    • CRPP/EPFL
    • EPFL-CRPP, Association Euratom-Conf\'ed\'eration Suisse, CH-1015 Lausanne, Switzerland

  • Basil Duval

    • CRPP/EPFL
    • EPFL CRPP
    • EPFL-CRPP, Association Euratom-Conf\'ed\'eration Suisse, CH-1015 Lausanne, Switzerland

  • Beno\^It Labit

    • CRPP/EPFL

  • Janos Marki

    • CRPP/EPFL

  • Sergei Yu Medvedev

    • Keldysh Institute of Applied Mathematics

  • Jean-Marc Moret

    • CRPP/EPFL
    • EPFL-CRPP, Association Euratom-Conf\'ed\'eration Suisse, CH-1015 Lausanne, Switzerland

  • Andreas Pitzschke

    • CRPP/EPFL

  • Olivier Sauter

    • CRPP/EPFL
    • EPFL-CRPP, Association Euratom-Conf\'ed\'eration Suisse, CH-1015 Lausanne, Switzerland
    • Ecole Polytechnique Federale de Lausanne, EPFL/CRPP, Association Euratom-Suisse, Switzerland