Comparison between a non-hydrostatic numerical model and analytic theory for the two-layer exchange flows

Recently, Armi and Riemenschneider (2008) improved the two-layer hydraulic theory and applied it to the co-located sill and contraction. The main goal in this study is to compare the new theory with a non-hydrostatic numerical model. To this end, the numerical model is employed for two different geometries. The first geometry is steep topography with co-located contraction and the second geometry is a much gentler slope so that the non-hydrostatic forces are reduced. It is found that the model captures the two control points, a topographic control at the crest and a virtual control on the dense reservoir side described by the theory. The flow is subcritical in between these control points. There is agreement between the modeled and analytical interface heights in the gentler topography.