 Publication Date:
 NSFPAR ID:
 10201987
 Journal Name:
 Journal of High Energy Physics
 Volume:
 2021
 Issue:
 3
 ISSN:
 10298479
 Sponsoring Org:
 National Science Foundation
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Numerous field observations of tsunamiinduced eddies in ports and harbours have been reported for recent tsunami events. We examine the evolution of a turbulent shallowwater monopolar vortex generated by a long wave through a series of largescale experiments in a rectangular wave basin. A leadingelevation asymmetric wave is guided through a narrow channel to form a flow separation region on the lee side of a straight vertical breakwater, which coupled with the transient flow leads to the formation of a monopolar turbulent coherent structure (TCS). The vortex flow after detachment from the trailing jet is fully turbulent ( $Re_h \sim O(10^{4}\text {}10^{5}$ )) for the remainder of the experimental duration. The free surface velocity field was extracted through particle tracking velocimetry over several experimental trials. The firstorder model proposed by Seol & Jirka ( J. Fluid Mech. , vol. 665, 2010, pp. 274–299) to predict the decay and spatial growth of shallowwater vortices fits the experimental data well. Bottom friction is predicted to induce a $t^{1}$ azimuthal velocity decay and turbulent viscous diffusion results in a $\sqrt {t}$ bulk vortex radial growth, where $t$ represents time. The azimuthal velocity, vorticity and free surface elevation profiles are well described through anmore »

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