Abstract
A criterion, allowing one to assess conditions likely togenerate gap flows and/or hydraulicjumps in stratified flows over a mountain ridge or a mountain pass,is derived. It is based on the one-dimensional reduced-gravity shallow-watertheory generalized to a three-dimensional orography with moderate streamwisevariations by introducing a variable effective flow cross-section. In this way,the hydraulic jump and gap flow are accommodated within the same model. Theresulting steady hyperbolic problem is shown to require the boundaryconditions to be expressed in terms of Riemann invariants. The latter yield the flow betweentwo given sites in a unique way. In particular, it is possible to relateunambiguously the existence of a hydraulic jump/gap flow and its energydiscontinuity to the boundary conditions. A simple method of flow interpolationand energy discontinuity calculation between two sites is presented.
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Drobinski, P., Dusek, J. & Flamant, C. Diagnostics Of Hydraulic Jump And Gap Flow In Stratified Flows Over Topography. Boundary-Layer Meteorology 98, 475–495 (2001). https://doi.org/10.1023/A:1018703428762
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DOI: https://doi.org/10.1023/A:1018703428762