HR: 16:30h
AN: OS24A-03    [Abstracts]
TI: Using a Navier-Stokes Solver to Drive a Discrete Particle Model for Sediment Transport in the Swash Zone
AU: * Calantoni, J
EM: joec@nrlssc.navy.mil
AF: Naval Research Laboratory, Code 7440.3, Stennis Space Center, MS 39529 United States
AU: Puleo, J A
EM: jpuleo@coastal.udel.edu
AF: Department of Civil and Environmental Engineering, Center for Applied Coastal Research University of Delaware, Newark, DE 19716 United States
AB: A volume of fluid Navier-Stokes solver for simulating inner surf and swash zone flows (RIPPLE) is used to drive a discrete particle model (DPM) for sediment transport. RIPPLE predicts the pressure gradient and fluid velocity in the horizontal and vertical directions providing the direct forcing for the hydrodynamics in the DPM. Coupling between RIPPLE and the DPM is one-way such that particle-particle and fluid-particle interactions do not provide direct feedback to the fluid phase. The fluid velocities are used to calculate the drag force on individual particles with the empirical drag law for spheres, while local pressure gradients also generate body forces on particles. Grain sizes used in simulations range from coarse sand to gravel. Cross-shore profiles of swash typically greater than 3 m are simulated. The number of particles used in simulations ranges from 10$^{3}$ to greater than 10$^{5}$. Flows with periods on the order of several seconds and wave heights up to 0.2 m are modeled. Preliminary simulations were performed with low particle concentrations and nearly-neutrally buoyant particles. These simulations represent tracers that interact with each other and the fixed-bed. Additional simulations with particles having more realistic sediment characteristics have been performed and demonstrate the suspension and advection of particles over several swash cycles. Implications of simulation results on the role of sediment advection on swash zone morphodynamics will be discussed.
DE: 4255 Numerical modeling
DE: 4546 Nearshore processes
DE: 4558 Sediment transport
DE: 3020 Littoral processes
DE: 3022 Marine sediments--processes and transport
SC: Ocean Sciences [OS]
MN: 2004 AGU Fall Meeting