Hostname: page-component-cd9895bd7-p9bg8 Total loading time: 0 Render date: 2024-12-28T15:42:12.143Z Has data issue: false hasContentIssue false

Laboratory and numerical experiments on the near wake of a sphere in a stably stratified ambient

Published online by Cambridge University Press:  21 December 2021

T.J. Madison
Affiliation:
Department of Aerospace and Mechanical Engineering, University of Southern California, Los Angeles, CA 90081, USA
X. Xiang
Affiliation:
Department of Aerospace and Mechanical Engineering, University of Southern California, Los Angeles, CA 90081, USA
G.R. Spedding*
Affiliation:
Department of Aerospace and Mechanical Engineering, University of Southern California, Los Angeles, CA 90081, USA
*
Email address for correspondence: [email protected]

Abstract

The flow around and behind a sphere in a linear density gradient has served as a model problem for both body-generated wakes in atmospheres and oceans, and as a means of generating a patch of turbulence that then decays in a stratified ambient. Here, experiments and numerical simulations are conducted for 20 values of Reynolds number, $Re$, and internal Froude number, $Fr$, where each is varied independently. In all cases, the early wake is affected by the background density gradient, notably in the form of the body-generated lee waves. Mean and fluctuating quantities do not reach similar states, and their subsequent evolution would not be collapsible under any universal scaling. There are five distinguishable flow regimes, which mostly overlap with previous literature based on qualitative visualisations and, in this parameter space, they maintain their distinguishing features up to and including buoyancy times of 20. The possible relation of the low $\{Re, Fr\}$ flows to their higher $\{Re, Fr\}$ counterparts is discussed.

Type
JFM Papers
Copyright
© The Author(s), 2021. Published by 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

REFERENCES

Abdilghanie, A.M. & Diamessis, P.J. 2013 The internal gravity wave field emitted by a stably stratified turbulent wake. J. Fluid Mech. 720, 104139.CrossRefGoogle Scholar
Achenbach, E. 1974 Vortex shedding from spheres. J. Fluid Mech. 62, 209221.CrossRefGoogle Scholar
Bevilaqua, P.M. & Lykoudis, P.S. 1978 Turbulence memory in self-preserving wakes. J. Fluid Mech. 89, 589606.CrossRefGoogle Scholar
Billant, P. & Chomaz, J.M. 2001 Self-similarity of strongly stratified inviscid flows. Phys. Fluids 13 (6), 16451651.CrossRefGoogle Scholar
Bonnier, M. & Eiff, O. 2002 Experimental investigation of the collapse of a turbulent wake in a stably stratified fluid. Phys. Fluids 14 (2), 791801.CrossRefGoogle Scholar
Brethouwer, G., Billant, P., Lindborg, E. & Chomaz, J.M. 2007 Scaling analysis and simulation of strongly stratified turbulent flows. J. Fluid Mech. 585, 343368.CrossRefGoogle Scholar
Brucker, K.A. & Sarkar, S. 2010 A comparative study of self-propelled and towed wakes in a stratified fluid. J. Fluid Mech. 652, 373404.CrossRefGoogle Scholar
de Bruyn Kops, S. & Riley, J. 2019 The effects of stable stratifiecation on the decay of initially isotropic homogenous tubulence. J. Fluid Mech. 860, 787821.CrossRefGoogle Scholar
Castiglioni, G., Sun, G. & Domaradzki, J.A. 2019 On the estimation of artificial dissipation and dispersion errors in a generic partial differential equation. J. Comput. Phys. 397, 108843.CrossRefGoogle Scholar
Chen, K.K. & Spedding, G.R. 2017 Boussinesq global modes and stability sensitivity, with applications to stratified wakes. J. Fluid Mech. 812, 11461188.CrossRefGoogle Scholar
Chomaz, J.-M., Bonetton, P., Butet, A. & Hopfinger, E.J. 1993 Vertical diffusion of the far wake of a sphere moving in a stratified fluid. Phys. Fluids 5 (11), 27992806.CrossRefGoogle Scholar
Chongsiripinyo, K., Pal, A. & Sarkar, S. 2017 On the vortex dynamics of flow past a sphere in $Re = 3700$ in a uniformly stratified fluid. Phys. Fluids 29, 020703.CrossRefGoogle Scholar
Chongsiripinyo, K. & Sarkar, S. 2020 Decay of turbulent wakes behind a disk in homogeneous and stratified fluids. J. Fluid Mech. 885, A31.CrossRefGoogle Scholar
Clift, R., Grace, J.R. & Weber, M.E. 1978 Bubbles Drops and Particles. Academic Press.Google Scholar
Diamessis, P.J., Gurka, R. & Liberzon, A. 2010 Spatial characterization of vortical structures and internal waves in a stratified turbulent wake using proper orthogonal decomposition. Phys. Fluids 22, 086601.CrossRefGoogle Scholar
Diamessis, P.J., Spedding, G.R. & Domaradzki, J.A. 2011 Similarity scaling and vorticity structure in high-Reynolds-number stably stratified turbulent wakes. J. Fluid Mech. 671, 5295.CrossRefGoogle Scholar
Dommermuth, D.G., Rottman, J.W., Innis, G.E. & Novikov, E.A. 2002 Numerical simulation of the wake of a towed sphere in a weakly stratified fluid. J. Fluid Mech. 473, 83101.CrossRefGoogle Scholar
Fletcher, C.A.J. 1991 Computational Techniques for Fluid Dynamics, vol. 1. Springer.Google Scholar
Gargett, A., Osborn, T. & Nasmyth, P 1984 Local isotropy and the decay of turbulence in a stratified fluid. J. Fluid Mech. 144, 231280.CrossRefGoogle Scholar
George, W.K. 1989 The self-preservation of turbulent flows and its relation to initial conditions and coherent structures. In Advances in Turbulence (ed. W.K. George & R.E.A. Arndt), pp. 39–73. Hemisphere.Google Scholar
Gibson, C.H. 1980 Fossil temperature, salinity and vorticity in the ocean. In Marine Turbulence (ed. J.C.T. Nihoul), pp. 221–258. Springer.CrossRefGoogle Scholar
Gibson, C.H, Chen, C.C & Lin, S.C 1968 Measurements of turbulent velocity and temperature fluctuations in the wake of a sphere. AIAA J. 6, 642649.CrossRefGoogle Scholar
Godoy-Diana, R., Chomaz, J.-M. & Billant, P. 2004 Vertical length scale selection for pancake vortices in strongly stratified viscous fluids. J. Fluid Mech. 504, 229238.CrossRefGoogle Scholar
Gourlay, M.J., Arendt, S.C., Fritts, D.C. & Werne, J. 2001 Numerical modeling of initially turbulent wakes with net momentum. Phys. Fluids 13, 37833802.CrossRefGoogle Scholar
Hanazaki, H. 1988 A numerical study of three-dimensional stratified flow past a sphere. J. Fluid Mech. 192, 393419.CrossRefGoogle Scholar
Johnson, T.A. & Patel, V.C. 1999 Flow past a sphere up to a Reynolds number of 300. J. Fluid Mech. 378, 1970.CrossRefGoogle Scholar
Kim, H.J. & Durbin, P.A. 1988 Observations of the frequencies in a sphere wake and of drag increase by acoustic excitation. Phys. Fluids 31, 32603265.CrossRefGoogle Scholar
Le Clair, B.P., Hamielec, A.E. & Pruppacher, H.R. 1970 A numerical study of the drag on a sphere at low and intermediate Reynolds numbers. J. Atmos. Sci. 27, 308315.2.0.CO;2>CrossRefGoogle Scholar
Lee, S. 2000 A numerical study of the unsteady wake behind a sphere in a uniform flow at moderate Reynolds numbers. Comput. Fluids 29, 639667.CrossRefGoogle Scholar
Lighthill, M.J. 1978 Waves in Fluids. Cambridge University Press.Google Scholar
Lin, Q., Boyer, D.L. & Fernando, H.J.S. 1992 Turbulent wakes of linearly stratified flow past a sphere. Phys. Fluids 4 (8), 16871696.CrossRefGoogle Scholar
Lindborg, E. 2006 The energy cascade in a strongly stratified fluid. J. Fluid Mech. 550, 207242.CrossRefGoogle Scholar
Lofquist, K.E. & Purtell, L.P. 1984 Drag on a sphere moving horizontally through a stratified liquid. J. Fluid Mech. 148, 271284.CrossRefGoogle Scholar
Magnaudet, J., Rivero, M. & Fabre, J. 1995 Accelerated flows past a rigid sphere or a spherical bubble. Part 1. Steady straing flow. J. Fluid Mech. 284, 97135.CrossRefGoogle Scholar
Métais, O. & Herring, J.R. 1989 Numerical simulations of freely evolving turbulence in stably stratified fluids. J. Fluid Mech. 202, 117148.CrossRefGoogle Scholar
Meunier, P., Diamessis, P.J. & Spedding, G.R. 2006 Self-preservation in stratified momentum wakes. Phys. Fluids 18, 106601.CrossRefGoogle Scholar
Meunier, P., Le Dizes, S., Redekopp, L.G. & Spedding, G.R. 2018 Internal waves generated by a stratified wake: experiment and theory. J. Fluid Mech. 846, 752788.CrossRefGoogle Scholar
Meunier, P. & Spedding, G.R. 2004 A loss of memory in stratified momentum wakes. Phys. Fluids 16, 298303.CrossRefGoogle Scholar
Meunier, P. & Spedding, G.R. 2006 Stratified propelled wakes. J. Fluid Mech. 552, 229256.CrossRefGoogle Scholar
Nastrom, G.D. & Gage, K.S. 1985 A climatology of atmospheric wavenumber spectra of wind and temperature observed by commercial aircraft. J. Atmos. Sci. 42, 950960.2.0.CO;2>CrossRefGoogle Scholar
Nastrom, G.D., Gage, K.S. & Jasperson, W.H. 1984 Kinetic energy spectrum of large- and mesoscale atmospheric processes. Nature 310, 3638.CrossRefGoogle Scholar
Nayar, K.G., Sharqawy, M.H., Banchik, L.D. & Lienhard, J.H. 2016 Thermophysical properties of seawater: a review and new correlations that include pressure dependence. Desalin. Water Treat. 390, 124.Google Scholar
Orr, T.S., Domaradzki, J.A., Spedding, G.R. & Constantinescu, G.S. 2015 Numerical simulations of the near wake of a sphere moving in a steady, horizontal motion through a linearly stratified fluid at $Re = 1000$. Phys. Fluids 27 (3), 035113.CrossRefGoogle Scholar
Ortiz-Tarin, J.L., Chongsiripinyo, K.C. & Sarkar, S. 2019 Stratified flow past a prolate spheroid. Phys. Rev. Fluids 4, 094803.CrossRefGoogle Scholar
Pal, A., Sarkar, S., Posa, A. & Balaras, E. 2016 Regeneration of turbulent fluctuations in low-Froude-number flow over a sphere at a Reynolds number of 3700. J. Fluid Mech. 804, R2.CrossRefGoogle Scholar
Pal, A., Sarkar, S., Posa, A. & Balaras, E. 2017 Direct numerical simulation of stratified flow past a sphere at subcritical Reynolds number of 3700 and moderate Froude number. J. Fluid Mech. 826, 531.CrossRefGoogle Scholar
Redford, J.A., Castro, I.P. & Coleman, G.N. 2012 On the universality of turbulent axisymmetric wakes. J. Fluid Mech. 710, 419452.CrossRefGoogle Scholar
Redford, J.A., Lund, T.S. & Coleman, G.N. 2015 A numerical study of a weakly stratified turbulent wake. J. Fluid Mech. 776, 568609.CrossRefGoogle Scholar
Riley, J.J. & de Bruyn Kops, S.M. 2003 Dynamics of turbulence strongly influenced by buoyancy. Phys. Fluids 15, 20472059.CrossRefGoogle Scholar
Rottman, J.W., Brucker, K.A., Dommermuth, D.G. & Broutman, D. 2010 Parameterization of the near-field internal wave field generated by a submarine. In Proc. 28th Symp. on Naval Hydrodynamics, p. 790. Office of Naval Research.Google Scholar
Rowe, K.L., Diamessis, P.J. & Zhou, Q 2020 Internal gravity wave radiation from a stratified turbulent wake. J. Fluid Mech. 888, A25.CrossRefGoogle Scholar
Sakamoto, H. & Hanui, H. 1995 The formation mechanism and shedding frequency of vortices from a sphere in uniform shear flow. J. Fluid Mech. 287, 151171.CrossRefGoogle Scholar
Schranner, F., Domaradzki, J.A., Hickel, S. & Adams, N. 2015 Assessing the numerical dissipation rate and viscosity in numerical simulation of fluid flows. Comp. Fluids 114, 8497.CrossRefGoogle Scholar
Spedding, G.R. 1997 The evolution of initially turbulent bluff-body wakes at high internal Froude number. J. Fluid Mech. 337, 283301.CrossRefGoogle Scholar
Spedding, G.R. 2001 Anisotropy in turbulence profiles of stratified wakes. Phys. Fluids 13 (8), 23612372.CrossRefGoogle Scholar
Spedding, G.R. 2002 Vertical structure in stratified wakes with high initial Froude number. J. Fluid Mech. 454, 71112.CrossRefGoogle Scholar
Spedding, G.R., Browand, F.K. & Fincham, A.M. 1996 a The long-time evolution of the initially turbulent wake of a sphere in a stable stratification. Dyn. Atmos. Ocean. 23, 171182.CrossRefGoogle Scholar
Spedding, G.R., Browand, F.K. & Fincham, A.M. 1996 b Turbulence, similarity scaling and vortex geometry in the wake of a towed sphere in a stably stratified fluid. J. Fluid Mech. 314, 53103.CrossRefGoogle Scholar
Tomboulides, A.G. & Orszag, S.A. 2000 Numerical investigation of transitional and weak turbulent flow past a sphere. J. Fluid Mech. 416, 4573.CrossRefGoogle Scholar
Townsend, A.A. 1976 The Structure of Turbulent Shear Flow, 2nd edn. Cambridge University Press.Google Scholar
Uberoi, M.S. & Freymuth, P. 1970 Turbulent energy balance and spectra of the axisymmetric wake. Phys. Fluids 13 (9), 22052210.CrossRefGoogle Scholar
Voisin, B. 1991 Internal wave generation in uniformly stratified fluids. Part 1. Green's function and point sources. J. Fluid Mech. 231, 439480.CrossRefGoogle Scholar
Voisin, B. 2007 Lee waves from a sphere in a stratified flow. J. Fluid Mech. 574, 273315.CrossRefGoogle Scholar
Watanabe, T., Riley, J.J., de Bruyn Kops, S.M., Diamessis, P.J. & Zhou, Q. 2016 Turbulent/non-turbulent interfaces in wakes in stably stratified fluids. J. Fluid Mech. 797, R1.CrossRefGoogle Scholar
Xiang, X., Madison, T.J., Sellappan, P. & Spedding, G.R. 2015 The turbulent wake of a towed grid in a stratified fluid. J. Fluid Mech. 775, 149177.CrossRefGoogle Scholar
Zhou, Q. & Diamessis, P.J. 2019 Large-scale characteristics of stratified wake turbulence at varying Reynolds number. Phys. Rev. Fluids 4, 084802.CrossRefGoogle Scholar