Scalar imaging velocimetry measurements of the velocity gradient tensor field in turbulent flows. I. Assessment of errors

Lester K. Su, Werner Dahm

Research output: Contribution to journalArticle

32 Citations (Scopus)

Abstract

The consept of flow field velocimetry based on scalar imaging measurements [Phys. Fluids A 4, 2191 (1992)] is here formulated in terms of an integral minimization implementation, where the velocity field u(x,t) is found by minimizing weighted residuals of the conserved scalar transport equation, along with the continuity condition and a smoothness condition. We apply this technique to direct numerical simulation (DNS) data for the limiting case of turbulent mixing of a Sc= 1 passive scalar field. The spatial velocity fields u(x,t) thus obtained demonstrate good correlation with the exact DNS fields, as do the statistics of the velocity and the velocity gradient fields. The results from this integral minimization implementation also show significant improvement over those from the direct inversion technique reported earlier. These results are shown to be largely insensitive to noise at levels characteristic of current fully resolved scalar field measurements.

Original languageEnglish (US)
Pages (from-to)1869-1882
Number of pages14
JournalPhysics of Fluids
Volume8
Issue number7
StatePublished - Jul 1996
Externally publishedYes

Fingerprint

Velocity measurement
turbulent flow
Turbulent flow
Tensors
tensors
scalars
Imaging techniques
gradients
Direct numerical simulation
direct numerical simulation
velocity distribution
optimization
turbulent mixing
continuity
Flow fields
flow distribution
Statistics
statistics
inversions
Fluids

ASJC Scopus subject areas

  • Fluid Flow and Transfer Processes
  • Computational Mechanics
  • Mechanics of Materials
  • Physics and Astronomy(all)
  • Condensed Matter Physics

Cite this

Scalar imaging velocimetry measurements of the velocity gradient tensor field in turbulent flows. I. Assessment of errors. / Su, Lester K.; Dahm, Werner.

In: Physics of Fluids, Vol. 8, No. 7, 07.1996, p. 1869-1882.

Research output: Contribution to journalArticle

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