HR: 0800h
AN: OS21B-1210    [Abstracts]
TI: Lagrangian Sediment Transport Model
AU: * Maderych, V
EM: vlad@env.kiev.ua
AF: Ukrainian Center of Environmental & Water Projects, Glushkov av. 42, Kiev, 03187 Ukraine
AU: Brovchenko, I
EM: brovchik@env.kiev.ua
AF: Ukrainian Center of Environmental & Water Projects, Glushkov av. 42, Kiev, 03187 Ukraine
AU: Fenical, S
EM: scott@coastharboreng.com
AF: Coast & Harbor Engineering, 110 Main St., Edmonds, WA 9020 United States
AU: Shepsis, V
EM: vladimir@coastharboreng.com
AF: Coast & Harbor Engineering, 110 Main St., Edmonds, WA 9020 United States
AB: A new two-dimensional Lagrangian sediment transport model was developed to simulate a wide-range of sediment transport processes, including sediment mobility under combined current and wave action, sediment transport and bed change under wave and currents effects, sediment transport patterns at nearshore coastal and offshore structures, and turbidity and sediment motion during dredging and dredged material placement. The Lagrangian technique was used to simulate transport of sediments, deposition, and re-suspension. The model can be applied to cohesive, non-cohesive, or mixed sediments. The sediment transport is simulated using bathymetry data, bed resistance characteristics, wave height and period, depth-averaged current velocity and bed material type, size and gradation, which vary throughout the model domain.The non-cohesive sediment transport model is based on a solution of two-dimensional mass conservation equations for the bed layer material and 2D equations for movement of sediment fractions either bed load or suspended load. The water column and bottom are divided into a set of layers: water layer, active layer, several active bed layers, and the bed layer. The model also takes into account the effects of armoring and changes in the bed composition. Cohesive sediments move entirely as suspended load in the water layer and sediment transport computations are based on a solution of the two-dimensional mass conservation equations for the bed layer material and two-dimensional equations for movement of sediment as suspended load. The water column and bed, as for non-cohesive sediments, was divided into a set of layers. Following the approach of Van Ledden (2002), the erosion of sediments made up of mud and sand mixtures is non-cohesive if the mud content is below a critical level. Above a critical mud content, the bed behaves cohesively. Deposition fluxes of mud and sand are independent. The sediment concentration in the water and active layer is represented by a collection of particles and the transport problem is solved as a particle tracking problem. The Graphical User Interface was designed to manage model input data, run the model using some predefined model input scenario and show model results. The model was tested and applied to the different coastal areas in the United States and the Ukraine. This study was sponsored by U.S. Civilian Research and Development Foundation (Project UM2-5013-KV-03).
DE: 4546 Nearshore processes
DE: 4558 Sediment transport
DE: 4560 Surface waves and tides (1255)
DE: 3020 Littoral processes
DE: 3022 Marine sediments--processes and transport
SC: Ocean Sciences [OS]
MN: 2004 AGU Fall Meeting