Extracting the turbulent flow-field from beam emission spectroscopy images using velocimetry.

Journal Article (Journal Article)

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 ∼10 and a zonal flow wavelength longer than ∼2 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.

Full Text

Duke Authors

Cited Authors

  • Kriete, DM; McKee, GR; Fonck, RJ; Smith, DR; Whelan, GG; Yan, Z

Published Date

  • October 2018

Published In

Volume / Issue

  • 89 / 10

Start / End Page

  • 10E107 -

PubMed ID

  • 30399767

Electronic International Standard Serial Number (EISSN)

  • 1089-7623

International Standard Serial Number (ISSN)

  • 0034-6748

Digital Object Identifier (DOI)

  • 10.1063/1.5036535

Language

  • eng