BORE-INDUCED MACROVORTICES OVER A PLANAR BEACH: THE CROSS-SEA CONDITION CASE
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Keywords

cross sea
ray theory
breaking
vorticity generation
Nonlinear Shallow Water Equations

How to Cite

Postacchini, M., Brocchini, M., & Soldini, L. (2012). BORE-INDUCED MACROVORTICES OVER A PLANAR BEACH: THE CROSS-SEA CONDITION CASE. Coastal Engineering Proceedings, 1(33), waves.18. https://doi.org/10.9753/icce.v33.waves.18

Abstract

Wave breaking over submerged topographic obstacles leads to vorticity generation and, at times, to the generation of strong offshore-directed rip currents. The generation of finite-length breakers may also be induced by the positive interaction of wave trains propagating to shore with a relative angle. Such an interaction gives rise to a short-crested system, this, in turn, generating both breakers of finite crossflow length and an intense associated vorticity. We here analyze such a vorticity generation mechanism specifically focusing on the location where wave breaking occurs. To this purpose we use both a simple theoretical approach, based on the well-known theory of wave ray propagation, and ad-hoc numerical simulations, by means of a NSWE (Nonlinear Shallow Water Equations) solver. A fair comparison between such preliminary theoretical and numerical results suggests that the present work can be used as the basis for future analyses of vorticity generation by cross seas.
https://doi.org/10.9753/icce.v33.waves.18
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References

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