Hostname: page-component-8448b6f56d-gtxcr Total loading time: 0 Render date: 2024-04-24T22:49:55.868Z Has data issue: false hasContentIssue false

Effects of rotation on convective turbulence

Published online by Cambridge University Press:  26 April 2006

Harindra J. S. Fernando
Affiliation:
Mechanical and Aerospace Engineering, Arizona State University, Tempe, AZ 85287-6106, USA
Rui-Rong Chen
Affiliation:
Mechanical Engineering, University of Wyoming, Laramie, WY 82071, USA
Don L. Boyer
Affiliation:
Mechanical Engineering, University of Wyoming, Laramie, WY 82071, USA Present address: Mechanical and Aerospace Engineering, Arizona State University, Tempe, AZ 85287-6106, USA.

Abstract

Laboratory experiments were carried out to investigate the effects of rotation on turbulent convection. The experimental facility was a bottom-heated, water-filled, cubical tank mounted on a turntable. The investigations were performed over a wide range of bottom buoyancy fluxes q0 and rotation rates Ω, including Ω = 0; q0 and Ω were held constant during each experiment. The depth of the water column H was fixed for the entire experimental programme. For the non-rotating experiments, the r.m.s. velocity fluctuations were found to scale well with the convective velocity $w_* = (q_0 H)^{\frac{1}{3}}$, while the mean and r.m.s. fluctuations of buoyancy were found to scale with q0/w*. The spectra of temperature fluctuations were measured and were used to assess the applicability of two types of scaling, one of which is advanced in the present study.

For the rotating experiments, the convective-layer growth is affected by the rotation at a height hc ≈ 4.5(q0Ω−3)½. The r.m.s. horizontal velocity of the rotationally affected mixed layer is uniform throughout the mixed layer and is given by $(\overline{u^{\prime 2}})^{\frac{1}{2}}_{\rm r}\approx 1.7(q_0\Omega^{-1})^{\frac{1}{2}}$. The time growth law of the mixed-layer thickness hr, when hr > hc, is given by hr ≈ 0.7(q0Ω−3)½Ωt, where t is the time. The rotational effects become important when the Rossby number is given by $Ro = (\overline{u^{\prime 2}})^{\frac{1}{2}}_{\rm r}/\omega l_{\rm r}\approx 1.5$, where the integral lengthscale is estimated as lr ≈ 0.25hc. The mean buoyancy gradient in the mixed layer was found to be much higher than in the corresponding non-rotating case, and the r.m.s. fluctuations and mean buoyancies were found to scale satisfactorily with (q0Ω)½. A spectral form for the temperature fluctuations in rotating convection is also proposed and is compared to the experimental results.

Type
Research Article
Copyright
© 1991 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

Adrian, F. J., Ferreira, R. T. D. S. & Boberg, T. 1986 Turbulent thermal convection in wide horizontal layers. Exps. Fluids 4, 121141.Google Scholar
Bardina, J., Ferziger, J. H. & Rogallo, R. S. 1985 Effect of rotation on isotropic turbulence: computation and modelling. J. Fluid Mech. 154, 321336.Google Scholar
Boubnov, B. M. & Golitsyn, G. S. 1986 Experimental study of convective structures in rotating fluids. J. Fluid Mech. 167, 503531.Google Scholar
Boubnov, B. M. & Golitsyn, G. S. 1988 Thermal structure and heat transfer of convection in a rotating fluid layer. Dolk. Acad. Nauk SSSR 300, 350353.Google Scholar
Boubnov, B. M. & Golitsyn, G. S. 1990 Temperature and velocity field regimes of convective motions in a rotating plane fluid layer. J. Fluid Mech. 219, 215239.Google Scholar
Boubnov, B. M. & Ivanov, V. N. 1988 Time dependent spectrum of temperature fluctuations for free turbulent convection in a fluid layer. Izv. Atmos. Ocean. Phys. 24, 361367.Google Scholar
Busse, F. H. & Heikes, K. E. 1980 Convection in a rotating layer; a simple case of turbulence. Science 208, 173174.Google Scholar
Castaing, B., Gunaratne, G., Heolot, G., Kadanoff, L., Libchaber, A., Thomae, S., Wu, X.-Z., Zaleski, S. & Aznetti, G. 1989 Scaling of hard thermal turbulence in Rayleigh–Bénard convection. J. Fluid Mech. 204, 130.Google Scholar
Caughey, S. J. 1982 Observed characteristics of the atmospheric boundary layer. In Atmospheric Turbulence and Air Pollution Modelling (ed. F. T. M. Nieuwstadt & H. VanDop) pp. 107158. D. Reidel.
Chandrasekhar, S. 1961 Hydrodynamic and Hydromagnetic Stability. Dover.
Chen, R., Fernando, H. J. S. & Boyer, D. L. 1989 Formation of isolated vortices in a rotating convecting fluid. J. Geophys. Res. 94, 1844518453.Google Scholar
Chen, C. F. & Johnson, D. H. 1984 Double diffusive convection: a report on an engineering foundation conference. J. Fluid Mech. 138, 405416.Google Scholar
Colin De Verdiere, A. 1980 Quasi-geostropic turbulence in a rotating turbulent fluid. Geophys. Astrophys. Fluid Dyn. 15, 213251.Google Scholar
Dang, K. & Roy, P. 1985 Direct and large-eddy simulation of homogeneous turbulence submitted to solid body rotation. Proc 5th Symp on Turbulent Shear Flows, Ithaca, NY.
Deardorff, J. W. 1970a Preliminary results from numerical investigations of the unstable boundary layer. J. Atmos. Sci. 27, 12091211.Google Scholar
Deardorff, J. W. 1970b Convective velocity and temperature scales for the unstable planetary boundary layer and for Rayleigh convection. J. Atmos. Sci. 27, 12111213.Google Scholar
Deardorff, J. W. 1972 Numerical investigation of the neutral and unstable planetary boundary layer. J. Atmos. Sci. 29, 91115.Google Scholar
Deardorff, J. W. 1985 Mixed-layer entrainment. A review. In 7th Symp. on turbulence and Diffusion, (ed. J. C. Weil), pp. 3942.
Deardorff, J. W. & Willis, G. E. 1985 Further results from a laboratory model of the convective planetary boundary layer. Boundary-Layer Met. 32, 205236.Google Scholar
Detering, H. W. & Etling, D. 1985 Application of k- model to the atmospheric boundary layer. Boundary-Layer met. 33, 113133.Google Scholar
Dickinson, S. C. & Long, R. R. 1983 Oscillating grid turbulence including the effects of rotation. J. Fluid Mech. 126, 315333.Google Scholar
Dikarev, S. N. 1983 On the influence of rotation on the convective structure in a deep homogeneous fluid. Dokl. Acad. Nauk. SSSR 273, 718720.Google Scholar
Fernando, H. J. S. 1987a The formation of layered structure when a stable salinity gradient is heated from below. J. Fluid Mech. 182, 525541.Google Scholar
Fernando, H. J. S. 1987b Comments on ‘Wind Direction and Equilibrium Mixed-Layer Depth: General Theory’. J. Phys. Oceanogr. 17, 169170.Google Scholar
Fernando, H. J. S., Boyer, D. L. & Chen, R. 1989 Turbulent thermal convection in rotating stratified fluids. Dyn. Atmos. Oceans 13, 95121.Google Scholar
Fluery, M., Mory, M., Hopfinger, E. J. & Auchere, D. 1991 Effects of rotation on turbulent mixing across density interface. J. Fluid Mech. 223, 165191.Google Scholar
Foster, T. D. 1971 Intermittent convection. J. Geophys. Fluid Dyn. 2, 201217.Google Scholar
Foster, T. D. & Waller, S. 1985 Experiments on convection at very high Rayleigh numbers. Phys. Fluids 28, 455461.Google Scholar
Golitsyn, G. S. 1980 Geostrophic convection. Dok. Acad. Nauk SSSR 251, 13561360.Google Scholar
Golitsyn, G. S. 1981 Structure of convection in rapid rotation. Dok. Acad. Nauk SSSR 261, 317320.Google Scholar
Hopfinger, E. J. 1987 Turbulence in stratified fluids: A review. J. Geophys. Res. 92, 52875303.Google Scholar
Hopfinger, E. J. 1989 Turbulence and vortices in rotating fluids. Theor. and Appl. Mech. (ed. P. Germain, M. Piau & D. Caillerie). Elsevier.
Hopfinger, E. J., Browand, F. K. & Gagne, Y. 1982 Turbulence and waves in a rotating tank. J. Fluid Mech. 125, 505534.Google Scholar
Hopfinger, E. J., Griffiths, R. W. & Mory, M. 1983 The structure of turbulence in homogeneous and stratified rotating fluids. J. Méc. Theor. Appl. 44, 2182.Google Scholar
Hopfinger, E. J. & Toly, J. A. 1976 Spatially decaying turbulence and its relation to mixing across density interfaces. J. Fluid Mech. 78, 155175.Google Scholar
Howard, L. N. 1963 Heat transport by turbulent convection. J. Fluid Mech. 17, 405432.Google Scholar
Howard, L. N. 1966 Convection at high Rayleigh number. In Applied Mechanics, Proc. 11th Congr. of Appl. Mech., Munich (ed. H. Görtler), pp. 11091115. Springer.
Hunt, J. C. R. 1984 Turbulence structure in thermal convection and shear-free boundary layers. J. Fluid Mech. 138, 161184.Google Scholar
Huppert, H. & Turner, J. S. 1981 Double diffusive convection. J. Fluid Mech. 106, 299329.Google Scholar
Ibbetson, A. & Tritton, D. J. 1975 Experiments on turbulence in a rotating fluid. J. Fluid Mech. 68, 639672.Google Scholar
Jacquin, L., Leuchter, O., Camdon, C. & Mathieu, J. 1990 Homogeneous turbulence in the presence of rotation. J. Fluid Mech. 220, 152.Google Scholar
Jacquin, L., Leuchter, O. & Geoffroy, P. 1989 Experimental study of homogeneous turbulence in the presence of rotation. In Turbulent Shear Flows 6 (ed. J.-C. Andre, J. Coustieux, F. Durst, B. E. Launder, F. W. Schmidt & J. H. Whitelaw), pp. 4657. Springer.
Kaimal, J. C., Wyngaard, J. C., Haugen, D. A., Cote, O. R., Izumi, Y., Caughey, S. J. & Readings, C. J. 1976 Turbulence structure in the convective boundary layer. J. Atmos. Sci. 33, 3946.Google Scholar
Lilly, D. K. 1968 Models of cloud-topped mixed layers under a strong inversion. Q. J. Roy. Met. Soc. 94, 292309.Google Scholar
Lundgren, T. S. 1985 The vertical flow above the drain-hole in a rotating vessel. J. Fluid Mech. 155, 381412.Google Scholar
Maxworthy, T., Hopfinger, E. J. & Redekopp, L. G. 1985 Wave motions in vortex cores. J. Fluid Mech. 151, 141165.Google Scholar
Mcewan, A. D. 1976 Angular momentum diffusion and the imitation of cyclones. Nature 260, 126128.Google Scholar
Monin, A. S. 1970 The atmospheric boundary layer. Ann. Rev. Fluid Mech. 2, 225250.Google Scholar
Mory, M. & Caperan, P. 1987 On the genesis of quasi-steady vortices in a rotating turbulent flow. J. Fluid Mech. 185, 121136.Google Scholar
Mory, M. & Hopfinger, E. J. 1988 Rotating turbulence evolving freely from an initial quasi 2-D state. In Macroscopic Modelling of Turbulent Flows (ed. U. Frish, J. B. Keller, G. Papanicolou & O. Pirenneau). Springer.
Nakagawa, Y. & Frenzen, P. 1955 A theoretical and experimental study of cellular convection in rotating fluid. Tellus 7, 121.Google Scholar
Rossby, H. T. 1969 A study of Bénard convection with and without rotation. J. Fluid Mech. 36, 309335.Google Scholar
Salmon, R. 1982 Geostropic turbulence. In Topics in Ocean Physics, (ed. R. Mallanotte-Rizzol & A. R. Osborne), . North-Holland.
Stubley, G. D. & Riopelle, G. 1988 The influence of earths rotation on planetary boundary-layer turbulence. Boundary-Layer Met. 45, 307324.Google Scholar
Tennekes, H. 1970 Free convection in the turbulent Ekman layer of the atmosphere. J. Atmos. Sci. 27, 10271034.Google Scholar
Tennekes, H. 1975 Eulerian and Lagrangian time microscales in isotropic turbulence. J. Fluid Mech. 67, 561567.Google Scholar
Thomas, D. B. & Townsend, A. A. 1957 Turbulent convection over a heated horizontal surface. J. Fluid Mech. 2, 473492.Google Scholar
Townsend, A. A. 1959 Temperature fluctuations over a heated horizontal surface. J. Fluid Mech. 5, 209241.Google Scholar
Traugott, S. C. 1958 Influence of solid body rotation on screen-produced turbulence. NACA TN 4135.Google Scholar
Turner, J. S. 1985 Multicomponent convection. Ann. Rev. Fluid Mech. 17, 11.Google Scholar
Turner, J. S. 1986 Turbulent entrainment: the development of the entrainment assumption, and its application to geophysical flows. J. Fluid Mech. 173, 431471.Google Scholar
Wigeland, R. A. & Nagib, H. M. 1978 Effect of rotation on decay of turbulence. Bull. Am. Phys. Soc. 23, 998, (also: IIT Fluids and Heat Transfer Rep. R78–1).Google Scholar
Willis, G. E. & Deardorff, J. W. 1984 A laboratory model of the unstable planetary boundary layer. J. Atmos. Sci. 31, 12971307.Google Scholar
Zeman, O. & Lumley, J. L. 1976 Modeling buoyancy driven mixed layers. J. Atmos. Sci. 33, 19741988.Google Scholar
Zimin, V. D. & Ketov, A. I. 1978 Turbulent convection in a cubic cavity heated from below. Izv. Acad. Nauk SSSR 4, 113138.Google Scholar