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A Modified Hypothesis on Turbulence Spectra in the Buoyancy Subrange of Stably Stratified Shear Flow
Author(s) -
Lin J.T.,
Panchev S.,
Cermak J. E.
Publication year - 1969
Publication title -
radio science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.371
H-Index - 84
eISSN - 1944-799X
pISSN - 0048-6604
DOI - 10.1029/rs004i012p01333
Subject(s) - buoyancy , turbulence , physics , dissipation , spectral line , turbulence modeling , power law , mechanics , stratified flow , shear flow , richardson number , inertial frame of reference , flow (mathematics) , classical mechanics , statistical physics , mathematics , thermodynamics , statistics , quantum mechanics
For a stationary process in the wave‐number range investigated (the buoyancy subrange of stably stratified flow) under the assumption of local homogeneity of the flow, two governing spectral equations derived from equations of motion and energy are solved by means of a generalized eddy‐viscosity approximation. Asymptotic solutions are obtained in the buoyancy subrange, where the local production and local dissipation of turbulence energy are negligible when compared with the inertial transfer and vertical heat‐flux terms when the flow conditions satisfy the frequency criterion[ ( g / T 0 ) ( d ‐ Γ ‐ / d z ) ] 1 / 2 ≪ [ N / ε ( g / T 0 ) 2 ] 1 / 2. The power law for the velocity and temperature spectra is not universal but varies with the flow conditions in the way ϕ( k ) ∼ k n and ϕ TT ( k ) ∼ k m , where −11/5 ≥ n ≥ −3 and −1 ≥ m ≥ −7/5.