Open AccessExperimental Evidence of the Kraichnan Scalar Spectrum at High Reynolds Numbers
Author(s) -
Darek Bogucki,
Haining Luo,
J. Andrzej Domaradzki
Publication year - 2012
Publication title -
journal of physical oceanography
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.706
H-Index - 143
eISSN - 1520-0485
pISSN - 0022-3670
DOI - 10.1175/jpo-d-11-0214.1
Subject(s) - reynolds number , wavenumber , scalar (mathematics) , spectral line , physics , mechanics , flow (mathematics) , turbulence , mathematics , geometry , optics , quantum mechanics
Measurements of horizontal temperature gradient spectra were carried out in a 25 m × 12 m × 3 m freshwater well mixed swimming pool. The associated flow Reynolds number was found to vary from 4 × 103 to 6 × 103. In all analyzed cases, at large wavenumbers k, the temperature gradient spectra exhibited behavior consistent with the Kraichnan spectral form: ~exp[−(6qk)1/2k] with constant . The measurements are in agreement with direct numerical simulations of a passive scalar flow with of Bogucki et al. and with recent experimental observations of Sanchez et al.