M. Oliver,
Justification of the shallow water limit for a rigid lid flow with bottom topography,
Theoretical and Computational Fluid Dynamics 9 (1997), 311-324.

Abstract:

The so-called lake equations arise as the shallow water limit of the rigid lid equations - three dimensional Euler equations with a rigid lid upper boundary condition - in a horizontally periodic basin with bottom topography. We prove an a priori estimate in the Sobolev space Hm for m>=3 which shows that a solution to the rigid lid equations can be approximated by a solution of the lake equations for an interval of time which can be estimated in terms of the initial deviation from a columnar configuration and the magnitude of the initial data in Hm, the gradient of the bottom topography in Hm+1, and the aspect ratio of the basin. In particular, any solution to the lake equations remains close to some solution of the rigid lid equations for an interval of time that can be made arbitrarily large by choosing the aspect ratio of the basin small.
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