Role of charge exchange neutrals in the deuterium retention for Tore Supra long discharges
In Tore Supra long pulses, particle balance gives evidence that a constant fraction of the injected gas is retained in the wall all along the shot (typically 50%), showing no sign of wall saturation after more than 6 minutes of discharge. During the discharge, the retention rate first decreases (phase 1), then remains constant throughout the pulse (phase 2). Phase 1 could be interpreted as implementation of particles combined with a constant codeposition rate, while phase 2 could correspond too codeposition alone, once the implanted surfaces are saturated with deuterium. This paper presents a possible contribution of charge exchange neutrals to the implantation process, based on modelling results with the Eirene neutral transport code. A complex pattern of particle implantation is evidenced, with saturation time constants ranging from less than one to several hundreds seconds, compatible with the experimental behaviour during phase 1.
Bibliographic Reference: An oral paper given at: 16th Int. Conf. on Plasma Surface Interaction in controlled Fusion Devices Organised by: Massachusetts Institute of Technology, Plasma Science & Fusion Center, Cambridge (US) Held at: Holiday Inn By The Bay, Portla
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: firstname.lastname@example.org
Record Number: 200417635 / Last updated on: 2004-07-13
Original language: en
Available languages: en