Large Eddy Simulation of turbulence generated by a weak breaking tidal bore
نویسندگان
چکیده
A tidal bore is a natural and fragile phenomenon, which is of great importance for the ecology of an estuary. The bore development is closely linked with the tidal range and the river mouth shape, and its existence is sensitive to any small change in boundary conditions. Despite their ecological and cultural value, little is known on the flow field, turbulent mixing and sediment motion beneath tidal bores. Indeed, some striking features can be highlighted in two-dimensional simulations, such as large velocity fluctuations and flow recirculation structures. Using Large Eddy Simulation method, the numerical results emphasised the complicated turbulent structures and their unsteadiness under a tidal bore.
منابع مشابه
Three-dimensional numerical simulation of the hydrodynamics generated by a weak breaking tidal bore
A tidal bore is a positive surge propagating upstream as the tidal flow turns to rising in river mouths exhibiting a converging funnelled channel forms during low freshwater conditions. While some recent laboratory experiments brought new insights to the turbulent motion generated by tidal bores, a numerical model based upon the Navier-Stokes equations is proposed to investigate the complicated...
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A numerical model was developed based on the Cubic-Interpolated Pseudo-particle (CIP) Combined Unified Procedure (CIP-CUP or C-CUP) method equipped with a Large Eddy Simulation (LES) model and a re-initialization method. The model was validated and applied to the tidal bore flow with a weak breaking front. In the tidal bore flow, the model equipped with a LES turbulence model reproduced accurat...
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0093-6413/$ see front matter 2009 Elsevier Ltd. A doi:10.1016/j.mechrescom.2009.09.008 * Corresponding author. Tel.: +33 (0) 540 003 307; E-mail addresses: [email protected] (P. Lubin), glock [email protected] (H. Chanson). A tidal bore is a natural and fragile phenomenon, which is of great importance for the ecology of an estuary. The bore development is closely linked with the tidal range and...
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