Entropy relaxation of ASDEX plasmas
This paper investigates the entropy relaxation in tokamak discharges in ASDEX. The plasma entropy is determined from the radial profiles of the electron density and temperature at different times and for time intervals in which the plasma entropy is approximately of the "water glass" type. In tokamak discharges with improved ohmic confinement (IOC) in ASDEX, a transition is observed from flat density profiles towards more peaked ones, while the normalised temperature profile is preserved. For this behaviour of the radial profiles it is shown that the entropy of the plasma increases during the IOC phase. Hence IOC and entropy relaxation are closely related. If the IOC phase is long enough, stationary plasma states are found which are compared with the relaxed state described in theory.
Bibliographic Reference: Report: IPP6/282 EN (1989)
Availability: Available from Max-Planck-Institut für Plasmaphysik, 8046 Garching bei München (DE)
Record Number: 199010675 / Last updated on: 1994-12-01
Original language: en
Available languages: en