International Association for Hydro-Environment Engineering and Research

IAHR, founded in 1935, is a worldwide independent member-based organisation of engineers and water specialists working in fields related to the hydro-environmental sciences and their practical application. Activities range from river and maritime hydraulics to water resources development and eco-hydraulics, through to ice engineering, hydroinformatics, and hydraulic machinery.
 You are here : eLibrary : IAHR World Congress Proceedings : 36th Congress - The Hague (2015) FULL PAPERS : THEME 3- SEDIMENT MANAGEMENT AND MORPHODYNAMICS : COUPLED SIMULATION OF FLOW, SEDIMENT TRANSPORT AND MORPHOLOGY EVOLUTION OVER RIPPLES BASED ON THE IM...
 COUPLED SIMULATION OF FLOW, SEDIMENT TRANSPORT AND MORPHOLOGY EVOLUTION OVER RIPPLES BASED ON THE IMMERSED BOUNDARY METHOD Author : GEORGIOS A. LEFTHERIOTIS , ATHANASSIOS A. DIMAS In the present study, numerical simulations of oscillatory flow over ripples, coupled with bed and suspended sediment transport, as well as the resulting morphology evolution, are performed. The simulations are based on the numerical solution of the Navier-Stokes equations for the flow and the advection-diffusion equation for the suspended load, while empirical formulas are used for the bed load. The bed morphological evolution is obtained by the numerical solution of the Exner equation. A fractional time-step scheme is used for the temporal discretization, while finite differences are used for the spatial discretization on a Cartesian grid. The Immersed Boundary method is implemented for the imposition of fluid and sediment boundary conditions on the moving bed surface. Three cases of mobility number were examined, ? = 4, 10, 3 40, at Reynolds number equal to 5?10 . The vortices generated on the lee side of the ripples are highly correlated with the behavior of the suspended sediment. Both suspended sediment concentration and bed load transport magnitude increase with increasing mobility parameter values. The evolution of suspended sediment is highly correlated to the vortical structures. File Size : 1,805,957 bytes File Type : Adobe Acrobat Document Chapter : IAHR World Congress Proceedings Category : 36th Congress - The Hague (2015) FULL PAPERS Article : THEME 3- SEDIMENT MANAGEMENT AND MORPHODYNAMICS Date Published : 18/04/2016 Download Now