Hostname: page-component-cd9895bd7-p9bg8 Total loading time: 0 Render date: 2024-12-17T21:47:01.640Z Has data issue: false hasContentIssue false
  • English
  • Français

Rotating gravity currents: small-scale and large-scale laboratory experiments and a geostrophic model

Published online by Cambridge University Press:  26 April 2007

P. J. THOMAS  and
P. F. LINDEN
P. J. THOMAS
Affiliation:
Fluid Dynamics Research Centre, School of Engineering, University of Warwick, Coventry, CV4 7AL, UK
P. F. LINDEN
Affiliation:
Department of Mechanical and Aerospace Engineering, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0411, USA
Get access Rights & Permissions [Opens in a new window]

Abstract

Laboratory experiments simulating gravity-driven coastal surface currents produced by estuarine fresh-water discharges into the ocean are discussed. The currents are generated inside a rotating tank filled with salt water by the continuous release of buoyant fresh water from a small source at the fluid surface. The height, the width and the length of the currents are studied as a function of the background rotation rate, the volumetric discharge rate and the density difference at the source. Two complementary experimental data sets are discussed and compared with each other. One set of experiments was carried out in a tank of diameter 1 m on a small-scale rotating turntable. The second set of experiments was conducted at the large-scale Coriolis Facility (LEGI, Grenoble) which has a tank of diameter 13 m. A simple geostrophic model predicting the current height, width and propagation velocity is developed. The experiments and the model are compared with each other in terms of a set of non-dimensional parameters identified in the theoretical analysis of the problem. These parameters enable the corresponding data of the large-scale and the small-scale experiments to be collapsed onto a single line. Good agreement between the model and the experiments is found.

Type
Papers
Information
Journal of Fluid Mechanics , Volume 578 , 10 May 2007 , pp. 35 - 65
Copyright
Copyright © Cambridge University Press 2007

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

REFRENCES

Avicola, G. & Huq, P. 2002 Scaling analysis for the interaction between a buoyant coastal current and the continental shelf: Experiments and observations. J. Phys. Oceanog. 32, 3233–3248.2.0.CO;2>CrossRefGoogle Scholar
Avicola, G. & Huq, P. 2003 a The role of the outflow geometry in the formation of the recirculating bulge region in coastal buoyant outflows. J. Mar. Res. 61, 411–434.CrossRefGoogle Scholar
Avicola, G. & Huq, P. 2003 b The characteristics of the recirculating bulge region in coastal buoyant outflows. J. Mar. Res. 61, 435–463.CrossRefGoogle Scholar
Batteen, M. L. 1997 Wind-forced modelling studies of currents, meanders, and eddies in the Californian current system. J. Geophys. Res. 102, 985–1010.CrossRefGoogle Scholar
Benjamin, T. B. 1968 Gravity currents and related phenomena. J. Fluid Mech. 31, 209–248.CrossRefGoogle Scholar
Blumberg, A. F., Signell, R. P. & Jenter, H. L. 1993 Modelling transport processes in the coastal ocean. J. Mar. Env. Engng 1, 31–52.Google Scholar
Bowman, M. J. & Iverson, R. L. 1978 Estuarine and plume fronts. In Workshop on Oceanic Fronts in Coastal Processes, Marine Sciences Research Centre, Stony Brook, NY, May 25–27, Proc., pp. 87–104. Springer.CrossRefGoogle Scholar
Boyer, D. L. & Davies, P. A. 2000 Laboratory studies of orographic effects in rotating and stratified flows. Annu. Rev. Fluid Mech. 32, 165–202.CrossRefGoogle Scholar
Boyer, D. L., Haidvogel, D. B. & Pérenne, N. 2001 Laboratory-numerical comparisons of flow over a coastal canyon. J. Atmos. Tech. 18, 1698–1718.Google Scholar
Chabert D'Hieres, G. Didelle, H. & Obaton, D. 1991 A laboratory study of surface boundary currents: Application to the Algerian Current. J. Geophys. Res. 96, 12539–12548.CrossRefGoogle Scholar
Davies, P. A., Jacobs, P. T. G. A. & Mofor, L. A. 1993 A laboratory study of buoyant fresh water boundary currents in tidal crossflows. Oceanologica Acta 16, 489–503.Google Scholar
Griffiths, R. W. 1986 Gravity currents in rotating systems. Annu. Rev. Fluid Mech. 18, 59–89.CrossRefGoogle Scholar
Griffiths, R. W. & Hopfinger, E. J. 1983 Gravity currents moving along a lateral boundary in a rotating fluid. J. Fluid Mech. 134, 357–399.CrossRefGoogle Scholar
Griffiths, R. W. & Linden, P. F. 1981 The stability of buoyancy-driven coastal currents. Dyn. Atmos. Oceans 5, 281–306.CrossRefGoogle Scholar
Hacker, J. N. & Linden, P. F. 2002 Gravity currents in rotating channels. Part 1. Steady-state theory. J. Fluid Mech. 457, 295–324.CrossRefGoogle Scholar
Hickey, B. M., Pietrafesa, L. J., Jay, D. A. & Boicourt, W. C. 1998 The Columbia River Plume Study: subtidal variability in the velocity and salinity fields. J. Geophys. Res. 103 (C5), 10339–10368.CrossRefGoogle Scholar
Hogg, N. G. & Johns, W. E. 1995 Western Boundary Currents, US National Report to International Union of Geodesy and Geophysics 1991–1994. Rev. Geophys., Supplement, 1311–1334.Google Scholar
Horner-Devine, A. R. Fong, D. A. Monismith, S. G. & Maxworthy, T. 2006 Laboratory experiments simulating coastal river inflow, J. Fluid Mech. 555, 203–232.CrossRefGoogle Scholar
Kawasaki, Y. & Sugimoto, T. 1984 Experimental studies on the formation and degeneration processes of the Tsugaru warm gyre. In Ocean Hydrodynamics of the Japan and East China Sea (ed. Ichiye, T.), pp. 225–238. D. Reidel.CrossRefGoogle Scholar
Lentz, S. J. & Helfrich, K. R. 2002 Buoyant gravity currents along a sloping bottom in a rotating fluid. J. Fluid Mech. 464, 251–278.CrossRefGoogle Scholar
Martin, J. R. & Lane-Serff, G. F. 2005 Rotating gravity currents. Part 1. Energy loss theory. J. Fluid Mech. 522, 35–62.CrossRefGoogle Scholar
Martin, J. R., Smeed, D. A. & Lane-Serff, G. F. 2005 Rotating gravity currents. Part 2. Potential vorticity theory. J. Fluid Mech. 522, 69–89.Google Scholar
Münchow, A. & Garvine, R. W. 1993 a Buoyancy and wind forcing of a coastal current. J. Mar. Res. 51, 293–322.CrossRefGoogle Scholar
Münchow, A. & Garvine, R. W. 1993 b Dynamical properties of a buoyancy-driven coastal current. J. Geophys. Res. 98 (C11), 20063–20077.CrossRefGoogle Scholar
Nof, D. & Pichevine, T. 2001 The ballooning of outflows. J. Phys. Oceanogr. 31, 3045–3058.2.0.CO;2>CrossRefGoogle Scholar
Rennie, S., Largier, J. L. & Lentz, S. J. 1999 Observations of low-salinity coastal current pulses downstream of Chesapeake Bay. J. Geophys. Res. 104 (C8), 18227–18240.CrossRefGoogle Scholar
Rivas, D., VelascoFuentes, O. U. Fuentes, O. U. & Ochoa, J. 2005 Topographic effects on the dynamics of gravity currents in a rotating system. Dyn. Atmos. Oceans 39, 227–249.CrossRefGoogle Scholar
Shin, J. O., Dalziel, S. B. & Linden, P. F. 2004 Gravity currents produced by lock exchange. J. Fluid Mech. 521, 1–34.CrossRefGoogle Scholar
Simpson, J. E. 1997 Gravity Currents in the Environment and the Laboratory, 2nd Edn. Cambridge University Press.Google Scholar
Stern, M. E., Whitehead, J. A. & Hua, B.-L. 1982 The intrusion of a density current along the coast of a rotating fluid. J. Fluid Mech. 123, 237–266.CrossRefGoogle Scholar
Thomas, P. J. & Linden, P. F. 1998 A bi-modal structure imposed on gravity-driven boundary currents in rotating systems by effects of the bottom topography. Exps. Fluids 25, 388–391.CrossRefGoogle Scholar