Hostname: page-component-cd9895bd7-q99xh Total loading time: 0 Render date: 2024-12-26T08:01:48.207Z Has data issue: false hasContentIssue false

Evolution of scalar spectra with the decay of turbulence in a stratified fluid

Published online by Cambridge University Press:  20 April 2006

A. E. Gargett
Affiliation:
Institute of Ocean Sciences, 9860 West Saanich Road, Sidney, B.C., Canada V8L 4B2

Abstract

Temperature measurements taken in association with the velocity measurements described by Gargett, Osborn & Nasmyth (1984) are examined. With careful noise removal the temperature dissipation spectrum is fully resolved and χ, the dissipation rate of temperature-fluctuation variance, is determined directly. With directly measured values of χ and ε, the turbulent-kinetic-energy dissipation rate per unit mass, the observed temperature spectra are non-dimensionalized by Oboukov–Corrsin–Batchelor scaling. Shapes and levels of the resulting non-dimensional spectra are then examined as functions of the degree of isotropy (measured) in the underlying velocity field. Two limiting cases are identified: Class A, associated with isotropic velocity fields; and Class B, associated with velocity fields which are anisotropic (owing to buoyancy forces repressing vertical relative to horizontal dimensions of energy-containing ‘eddies’). The present observations suggest that the Corrsin–Oboukov–Batchelor theory does not provide a universal description of the spectrum of temperature fluctuations in water. Class A scalar spectra have neither $k^{-\frac{5}{3}}$ nor k−1 subranges: a Batchelor-spectrum fit to the high-wavenumber roll-off region yields a value of 12 for the ‘universal’ constant q. In striking contrast, the buoyancy-affected Class B spectra exhibit a clear $k^{-\frac{5}{3}}$ subrange, an approach to a k−1 subrange, and a value of q ∼ 4 which is in rough agreement with most previous estimates. Previous oceanic and atmospheric measurements are re-examined in the light of the present results. It is suggested that these previous results are also affected by vertical scale limitation. Reasons underlying the discrepancies between theories and observations are discussed: these may be different in the two classes presented.

Type
Research Article
Copyright
© 1985 Cambridge University Press

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Antonia, R. A. & Van Atta, C. W. 1975 On the correlation between temperature and velocity dissipation fields in a heated turbulent jet. J. Fluid Mech. 67, 273288.Google Scholar
Batchelor, G. K. 1959 Small-scale variation of convected quantities like temperature in turbulent fluid. J. Fluid Mech. 5, 113133.Google Scholar
Batchelor, G. K. & Townsend, A. A. 1948 Decay of isotropic turbulence in the initial period. Proc. R. Soc. Lond. A 193, 539558.Google Scholar
Boston, N. E. J. & Burling, R. W. 1972 An investigation of high-wavenumber temperature and velocity spectra in air. J. Fluid Mech. 55, 473492.Google Scholar
Champagne, F. H., Friehe, C. A., Larue, J. C. & Wyngaard, J. C. 1977 Flux measurements, flux estimation techniques and fine-scale turbulence measurements in the unstable surface layer over land. J. Atmos. Sci. 34, 515530.Google Scholar
Corrsin, S. 1951 On the spectrum of isotropic temperature fluctuations in isotropic turbulence. J. Appl. Phys. 22, 469473.Google Scholar
Crawford, W. R. 1985 A comparison of lengthscales and decay times of turbulence in stably stratified flows. J. Fluid Mech. (submitted)Google Scholar
Dillon, T. M. 1982 Vertical overturns: a comparison of Thorpe and Ozmidov length scales. J. Geophys. Res. 87, 96019613.Google Scholar
Dillon, T. M. & Caldwell, D. R. 1980 The Batchelor spectrum and dissipation in the upper ocean. J. Geophys. Res. 85, 19101916.Google Scholar
Dougherty, J. P. 1961 The anisotropy of turbulence at the meteor level. J. Atmos. Terr. Phys. 21, 210213.Google Scholar
Farmer, D. M. & Smith, J. D. 1980 Tidal interaction of stratified flow with a sill in Knight Inlet. Deep-Sea Res. 27A, 239254.Google Scholar
Gargett, A. E. 1980 Data Report and calibrations of turbulence measurements in Knight Inlet, B.C. from the PISCES IV submersible: November 1978. Pacific Marine Sci. Rep. 80–6. Institute of Ocean Sciences, Patricia Bay, P.O. Box 6000, Sidney, B.C., Canada. 71 pp.
Gargett, A. E., Hendricks, P. J., Sanford, T. B., Osborn, T. R. & Williams, A. J. 1981 A composite spectrum of vertical shear in the upper ocean. J. Phys. Oceanogr. 11, 12581271.Google Scholar
Gargett, A. E., Osborn, T. R. & Nasmyth, P. W. 1984 Local isotropy and the decay of turbulence in a stratified fluid. J. Fluid Mech. 144, 231280.Google Scholar
Gibson, C. H. & Schwarz, W. H. 1963 The universal equilibrium spectra of turbulent velocity and scalar fields. J. Fluid Mech. 16, 365384.Google Scholar
Gibson, C. H., Stegen, G. R. & Mcdonnell, S. 1970 Measurements of the universal constant in Kolmogoroff's Third Hypothesis for high Reynolds number turbulence. Phys. Fluids 13, 24482451.Google Scholar
Gibson, C. H., Stegen, G. R. & Williams, R. B. 1970 Statistics of the fine structure of turbulent velocity and temperature fields measured at high Reynolds number. J. Fluid Mech. 41, 153167.Google Scholar
Grant, H. L., Hughes, B. A., Vogel, W. M. & Moilliet, A. 1968 The spectrum of temperature fluctuations in turbulent flow. J. Fluid Mech. 34, 423442.Google Scholar
Grant, H. L., Stewart, R. W. & Moilliet, A. 1962 Turbulence spectra from a tidal channel. J. Fluid Mech. 12, 241263.Google Scholar
Gregg, M. C. & Sanford, T. B. 1980 Signatures of mixing from the Bermuda Slope, the Sargasso Sea and the Gulf Stream. J. Phys. Oceanogr. 10, 105127.Google Scholar
Heskestad, G. 1965 A generalized Taylor hypothesis with application for high Reynolds number turbulent shear flows. Trans. ASME E: J. Appl. Mech. 87, 735740.Google Scholar
Hill, R. J. 1978 Models of the scalar spectrum for turbulent advection. J. Fluid Mech. 88, 541562.Google Scholar
Holloway, G. & Kristmannsson, S. S. 1984 Stirring and transport of tracer fields by geostrophic turbulence. J. Fluid Mech. 141, 3750.Google Scholar
Kaimal, J. C., Wyngaard, J. C., Izumi, Y. & Coté, O. R. 1972 Spectral characteristics of surface-layer turbulence. Q. J. R. Met. Soc. 98, 563589.Google Scholar
Kraichnan, R. H. 1968 Small-scale structure of a scalar field convected by turbulence. Phys. Fluids 11, 945953.Google Scholar
Kolmogoroff, A. N. 1941 The local structure of turbulence in an incompressible viscous fluid for very large Reynolds number. C.R. Acad. Sci. USSR 30, 301305.Google Scholar
Kolmogoroff, A. N. 1962 A refinement of previous hypotheses concerning the local structure of turbulence in a viscous incompressible fluid at high Reynolds number. J. Fluid Mech. 13, 8285.Google Scholar
Lange, R. E. 1982 An experimental study of turbulence behind towed biplanar grids in a salt-stratified fluid. J. Phys. Oceanogr. 12, 15061513.Google Scholar
Lesieur, M. & Herring, J. 1985 Diffusion of a passive scalar in two-dimensional turbulence. J. Fluid Mech. Submitted.Google Scholar
Lumley, J. L. 1965 Interpretation of time spectra measured in high intensity shear flows. Phys. Fluids 8, 10561062.Google Scholar
Mestayer, P. 1982 Local isotropy in a high-Reynolds-number turbulent boundary layer. J. Fluid Mech. 125, 475503.Google Scholar
Monin, A. S. & Yaglom, A. M. 1975 Statistical Fluid Mechanics, Vol. 2. MIT Press. 874 pp.
Oakey, N. S. 1982 Determination of the rate of dissipation of turbulent energy from simultaneous temperature and velocity shear microstructure measurements. J. Phys. Oceanogr. 12, 256271.Google Scholar
Oboukov, A. M. 1949 Structure of the temperature field in a turbulent flow. Izv. Akad. Nauk SSSR Ser. Geogr. i Geofiz. 13, 5869.Google Scholar
Oboukov, A. M. 1962 Some specific features of atmospheric turbulence. J. Fluid Mech. 13, 7781.Google Scholar
Ozmidov, R. V. 1965 On the turbulent exchange in a stably stratified ocean. Izv. Atmos. & Oceanic Phys. Ser. 1, 853860.Google Scholar
Paquin, J. E. & Pond, S. 1971 The determination of the Kolmogoroff constants of velocity, temperature and humidity fluctuations from second- and third-order structure functions. J. Fluid Mech. 50, 257269.Google Scholar
Phillips, O. M. 1977 The Dynamics of the Upper Ocean, 2nd Edn. Cambridge University Press. 336 pp.
Schmitt, K. F., Friehe, C. A. & Gibson, C. H. 1978 Humidity sensitivity of atmospheric temperature sensors by salt contamination. J. Phys. Oceanogr. 8, 151161.Google Scholar
Stewart, R. W. 1969 Turbulence and waves in a stratified atmosphere. Radio Sci. 4, 12691278.Google Scholar
Stillinger, D. C., Helland, K. N. & Van Atta, C. W. 1983 Experiments on the transition of homogeneous turbulence to internal waves in a stratified fluid. J. Fluid Mech. 131, 91122.Google Scholar
Tennekes, H. & Lumley, J. L. 1972 A First Course in Turbulence. MIT Press. 300 pp.
Van Atta, C. W. 1971 Influence of fluctuations in local dissipation rates on turbulent scalar characteristics in the inertial subrange. Phys. Fluids 14, 18031804.Google Scholar
Van Atta, C. W. 1973 Erratum: Influence of fluctuations in local dissipation rates on turbulent scalar characteristics of the inertial subrange. Phys. Fluids 16, 574.Google Scholar
Weiler, H. S. & Burling, R. W. 1967 Direct measurements of stress and spectra of turbulence in the boundary layer over the sea. J. Atmos. Sci. 24, 653664.Google Scholar
Williams, R. M. & Paulson, C. A. 1977 Microscale temperature and velocity spectra in the atmospheric boundary layer. J. Fluid Mech. 83, 547567.Google Scholar
Wyngaard, J. C. & Pao, Y. H. 1971 Some measurements of the fine structure of large Reynolds number turbulence. In Statistical Models and Turbulence (ed. M. Rosenblatt & C. Van Atta). Lecture Notes in Physics vol. 12, Springer.
Yaglom, A. M. 1966 The influence of fluctuations in energy dissipation on the shape of turbulence characteristics in the inertial interval. Sov. Phys. Dokl. 11, 26.Google Scholar