State Water Resources Research Institute Program (WRRI)

Details for Project ID 2009LA60B, 2010

Modeling Turbulent Enhancement of Sediment Transport

Institute: Louisiana
Start Date: 2009-03-01 End Date: 2010-09-30
Total Federal Funds: $17,973 Total Non-Federal Funds: $41,017

Principal Investigators: Heather Smith

Abstract: The accurate prediction of sediment transport in coastal environments is key to the sustainability and ecological growth of the Louisiana coast. Our ability to simulate these phenomena is limited to our current understanding and the development of mathematical frameworks to describe these processes. In addition to the traditional approach of describing movement with an excess applied shear, processes such as externally generated turbulence and wave driven pressure gradients can increase transport significantly. In numeric simulations, two scales of turbulence can be considered: the resolvable vortex motions and the parametrized turbulent fluctuations. While the complexity of engineering models has increased due to the availability of computation power, sediment transport calculations still rely on a combination of spatial and temporal averages. This research will explore the relationship between the applied bed stress and the numerically predicted contributions from the turbulence closure scheme. Simulations performed in this research will resolve the larger scale vortex motions, and both the two-equation k-ϵ and Large Eddy Simulation closure schemes will be considered. The modeled bed stress and external flow field will be compared with a variety of available laboratory data. This analysis will provide insight to the adequacy of averaged models.