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Lock Exchnage test case

Ocean Models

This test case is described in a closed area, with two layers of fluid at rest, with different densities, separated by a vertical wall. At the initial moment, thewall is removed and the system evolves under the action of gravity only. It does not consider any coriolis force, friction at the bottom or mixing processes.

Here the field is a flat bottom "tank" in 2D vertical geometry, with an horizontal extension of 65 km to a depth of 20m. The discretization of 130 points based on 20 points horizontal and the vertical. The difference in density is achieved by a difference in salinity between 7.1 psu fluids. The simulation represents a period of 12h.

The initial density field is:

Intial density state for the Lock Exchange experiment

Inserting the movie here!

Usefull files to rerun the Lock Exchange test case:

  • Fortran subroutine (to be unzip into the UDIR directory)
  • The notebooks


  •  Benjamin T. B. Gravity currents and related phenomena. J. of Fluid Mech., 31:209-248, 1968.
  •  Haidvogel D. B. and A. Beckmann. Numericla ocean circulation modeling of series on environment science and management, vol 2. Imperial College Press, London, 1999.
  •  Kolar R. L., T. C. G. Kibbey, C. M. Szpilka, K. M. Dresback, E. M. Tromble, I. P. Toohey, J. L. Hoggan and J. H. Atkinson.Process-oriented tests for validation of a baroclinic shallow water models: The lock-exchnage problem. Ocean Modelling, 28:137-152, 2009.