0029733 - ÚFP 2006 RIV NL eng J - Journal Article
Sánchez, E. - Hidalgo, C. - Goncalves, B. - Silva, C. - Pedrosa, M. A. - Hron, Martin - Erents, K.
On the energy transfer between flows and turbulence in the plasma boundary of fusion devices.
[Přenos energie mezi toky v plazmatu a turbulencí na okraji fúzních zařízení.]
Journal of Nuclear Materials. 337-339, - (2005), s. 296-300. ISSN 0022-3115. E-ISSN 1873-4820
Institutional research plan: CEZ:AV0Z20430508
Keywords : radial electric fields * turbulence * fluctuations * Langmuir probe * JET
Subject RIV: BL - Plasma and Gas Discharge Physics
Impact factor: 1.414, year: 2005

The energy transfer between perpendicular flows and turbulence has been investigated in the JET plasma boundary region. The energy transfer from DC flows to turbulence, directly related with the momentum flux (e.g. vq vr) and the radial gradient in the flow, can be both positive and negative in the proximity of sheared flows. The direct computation of the turbulent viscosity gives values comparable to the anomalous particle diffusivity (in the order of 1m2/s). Furthermore, this energy transfer rate is comparable with the mean flow kinetic energy normalized to the correlation time of turbulence, implying that this energy transfer is significant. These results show, for the first time, the dual role of turbulence as a damping (eddy viscosity) and driving of flows in fusion plasmas emphasizing the important role of turbulence to understand perpendicular dynamics in the plasma boundary region of fusion plasmas.

Přenos energie mezi toky v plazmatu, kolmými k siločarám magnetického pole, a turbulencí byl zkoumán v okrajovém plazmatu tokamaku JET. Získaná turbulentní viskozita dává hodnoty obdobné anamální difuzivitě, rychlost přenosu energie je srovnatelná se střední kinetickou energií normalizovanou na korelační dobu turbulence. Výsledek poprvé ukazuje na duální roli turbulence jako prostředku tlumení turbulence i jako jejího buzení.
Permanent Link: http://hdl.handle.net/11104/0119537