ASDEX simulation calculations with simple transport laws
Simulation calculations with simple models of radius-, density- and temperature-dependent transport laws were carried out in order to establish deviations from the expected relation between local and global confinement trends. These calculations correspond to fictitious density and heating power scans, but they use realistic parameter ranges, device properties and NBI-system specifications of ASDEX. They aim to describe only Ohmic- and L-regime discharges and are restricted in additional heating to neutral injection, for which a validated power deposition model is readily available. The results of the simulations show that heat deposition and fast particle contributions to the total energy content can significantly affect the apparent scaling of global confinement times with density and power. In particular the weak or absent density dependence of confinement times in NBI-heated discharges needs not necessarily conflict with predictions of transport models based on strong electrostatic turbulence in the collision-free regions.
Bibliographic Reference: Report: IPP 5/28 EN (1989) 13 pp.
Availability: Available from Max-Planck-Institut für Plasmaphysik, 8046 Garching-bei-München (DE)
Record Number: 199010332 / Last updated on: 1994-12-01
Original language: en
Available languages: en