Community Research and Development Information Service - CORDIS

Abstract

The time evolution of the plasma current during a tokamak disruption is calculated by solving the equations for runaway electron production simultaneously with the induction equation for the toroidal electric field. The resistive diffusion time in a post-disruption plasma is typically comparable to the runaway avalanche growth time. Accordingly, the toroidal electric field induced after the thermal quench of a disruption diffuses radially through the plasma at the same time as it accelerates runaway electrons, which in turn back-react on the electric field. When these processes are accounted for in a self-consistent way, it is found that (1) the efficiency and time scale of runaway generation agrees with JET experiments; (2) the runaway current profile typically becomes more peaked than the pre-disruption current profile; and (3) can easily become radially filamented. It is also shown that higher runaway electron generation is expected if the thermal quench is sufficiently fast.

Additional information

Authors: HELANDER P, EURATOM-UKAEA Fusion Association, Culham Science Centre, Abingdon (GB);ANDERSSON F, Chalmers University of Technology and EURATOM-VR Assocation, Goteborg (SE);FULOP T, Chalmers University of Technology and EURATOM-VR Assocation, Goteborg (SE);SMITH H, Chalmers University of Technology and EURATOM-VR Assocation, Goteborg (SE);ANDERSON D, Chalmers University of Technology and EURATOM-VR Assocation, Goteborg (SE);LISAK M, Chalmers University of Technology and EURATOM-VR Assocation, Goteborg (SE);ERIKSSON L-G, Departement de Recherches sur la Fusion Controlee, Association Euratom-CEA sur la Fusion, CEA Cadarache, Saint-Paul-lez-Durance (FR)
Bibliographic Reference: An oral paper given at: 20th IAEA Fusion Energy Conference Organised by: International Atomic Energy Agency Held at: Centrtro de Fusao Nuclear, Vilamoura (PT)
Availability: Available from Association EURATOM-CEA, Departement de Recherches sur la Fusion Controlee, CEA Cadarache, F-13108 St Paul-Lez-Durance, France Tel: (+33) 4 42 25 70 01; Fax: (+33) 4 42 25 64 21 E-mail: dirdrfc@drfc.cad.cea.fr
Follow us on: RSS Facebook Twitter YouTube Managed by the EU Publications Office Top