caa a22 4500 445874686 CHVBK 20180317145524.0 cr unu---uuuuu 170323e20110801xx s 000 0 eng 10.1007/s10652-010-9189-5 doi (NATIONALLICENCE)springer-10.1007/s10652-010-9189-5 Chanson Hubert Professor in Civil Engineering, The University of Queensland, 4072, Brisbane, QLD, Australia aut Undular tidal bores: effect of channel constriction and bridge piers [Elektronische Daten] [Hubert Chanson] A tidal bore may occur in a macro-tidal estuary when the tidal range exceeds 4.5-6 m and the estuary bathymetry amplifies the tidal wave. Its upstream propagation induces a strong mixing of the estuarine waters. The propagation of undular tidal bores was investigated herein to study the effect of bridge piers on the bore propagation and characteristics. Both the tidal bore profile and the turbulence generated by the bore were recorded. The free-surface undulation profiles exhibited a quasi-periodic shape, and the potential energy of the undulations represented up to 30% of the potential energy of the tidal bore. The presence of the channel constriction had a major impact on the free-surface properties. The undular tidal bore lost nearly one third of its potential energy per surface area as it propagated through the channel constriction. The detailed instantaneous velocity measurements showed a marked effect of the tidal bore passage suggesting the upstream advection of energetic events and vorticity "clouds” behind the bore front in both channel configurations: prismatic and with constriction. The turbulence patches were linked to some secondary motions and the proposed mechanisms were consistent with some field observations in the Daly River tidal bore. The findings emphasise the strong mixing induced by the tidal bore processes, and the impact of bridge structures on the phenomenon. Springer Science+Business Media B.V., 2010 Undular tidal bores nationallicence Free-surface undulations nationallicence Channel constriction nationallicence Bridge piers nationallicence Experimental measurements nationallicence Turbulent events nationallicence Macro-turbulence nationallicence Environmental Fluid Mechanics Springer Netherlands 11/4(2011-08-01), 385-404 1567-7419 11:4<385 2011 11 10652 https://doi.org/10.1007/s10652-010-9189-5 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10652-010-9189-5 text/html Onlinezugriff via DOI NATIONALLICENCE 100 1- Chanson Hubert Professor in Civil Engineering, The University of Queensland, 4072, Brisbane, QLD, Australia aut NATIONALLICENCE 773 0- Environmental Fluid Mechanics Springer Netherlands 11/4(2011-08-01), 385-404 1567-7419 11:4<385 2011 11 10652 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer