Earth Surface Materials: Multiscale Modeling of Bedload Transport, Erosion and Deposition of Non-uniform Material: From the Grain to the Field Scale

Abstract

The technical objective of the proposed effort is to provide insight into the dynamical evolution of sedimentary systems. The proposed effort seeks to achieve the stated technical objective using a combined approach of (1) discrete element method (DEM) modeling and (2) morphodynamic modeling. In (1), computational simulations will be performed using a model that has been developed by PI Hill and that represents segregation and bedload transport details such as the functional dependence of bedload transport on applied shear stress and the mobilization of a coarse gravel bed through the addition of finer particles. Random local variations of the fluid velocities scaled with published measured variation of turbulent fluctuations in a fully developed open channel flow will be introduced. Next, simulations will be performed that account for the scale of measured structures that have been determined to be significant in experimental studies of sediment transport in channels. In (2), a framework to capture the short-term variability of bed elevations and sediment fluxes will be employed. Specifically, the short-term changes in bed elevation associated with sediment transport and bedform migration will be modeled in terms of probability functions of bed elevation. The governing equations will be the shallow water equations of conservation of mass and momentum for the flow and the elevation-specific equation of sediment mass conservation in the bed deposit. Finally, the performances of the statistically based morphodynamic model will be tested by comparing numerical and experimental predictions from the literature of flow characteristics, bed elevation and fraction of tracer stones in a deposit.

Document Details

Document Type
DoD Grant Award
Publication Date
Jan 12, 2017
Source ID
W911NF1610337

Entities

People

  • Enrica Viparelli

Organizations

  • Army Contracting Command
  • United States Army
  • University of South Carolina

Tags

Readers

  • Coastal Oceanography
  • Computational Fluid Dynamics (CFD)
  • Geotechnical Engineering.