Extracting the turbulent flow-field from beam emission spectroscopy images using velocimetry.
Rev Sci Instrum
; 89(10): 10E107, 2018 Oct.
Article
em En
| MEDLINE
| ID: mdl-30399767
ABSTRACT
The 2D turbulent E × B flow-field is inferred from density fluctuation images obtained with the beam emission spectroscopy diagnostic on DIII-D using the orthogonal dynamic programming velocimetry algorithm. A synthetic turbulence model is used to test the algorithm and optimize it for measuring zonal flows. Zonal flow measurements are found to require a signal-to-noise ratio above â¼10 and a zonal flow wavelength longer than â¼2 cm. Comparison between the velocimetry-estimated flow-field and the E × B flow-field using a nonlinear gyrokinetic GENE simulation finds that the flow-fields have identical spatial structure and differ only by the mean turbulence phase velocity, which is spatially uniform in this flux tube simulation.
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Base de dados:
MEDLINE
Idioma:
En
Revista:
Rev Sci Instrum
Ano de publicação:
2018
Tipo de documento:
Article
País de afiliação:
Estados Unidos