Community Research and Development Information Service - CORDIS

Abstract

The parameters and processes governing the low and high (L and H) confinement in ASDEX are investigated by computer modelling. The L transport is shown to be connected with the non-Ohmic electron heating. After neutral injection, the L phase is maintained by the ion electron energy transfer rate for the significant time span of about 100 ms. It is found that the profile parameters eta-e,i = d ln T-e,i/d 1n n discriminate between the L transport and the H transport. Small $gh values around unity characterize the H regime, while larger eta values correspond to the L regime. The operational limits of the H-mode are connected with variations of eta-e and eta-i due to changes in the injection heating profile. These results suggest that drift instabilities such as dissipative trapped electron modes are involved in the anomalous L and H transport.

Additional information

Authors: BECKER G MAX-PLANCK-INSTITUT FUER PLASMAPHYSIK, GARCHING BEI MUENCHEN (GERMANY), MAX-PLANCK-INSTITUT FUER PLASMAPHYSIK, GARCHING BEI MUENCHEN (GERMANY)
Bibliographic Reference: NUCLEAR FUSION, VOL. 26 (1986), NO. 4, PP. 415-423
Record Number: 1989125044100 / Last updated on: 1987-07-01
Category: PUBLICATION
Available languages: en