Toward modeling turbulent suspension of sand in the nearshore
MetadataShow full item record
We present two depth- and phase-resolving models, based on single- and two-phase approaches for suspended sediment transport under water waves. Both models are the extension of a wave hydrodynamic model Cornell Breaking Wave and Structure (COBRAS). In the two-phase approach, dilute two-phase mass and momentum equations are calculated along with a fluid turbulence closure based on balance equations for the fluid turbulence kinetic energy k f and its dissipation rate ε f . In the single-phase approach the fluid flow is described by the Reynolds-Averaged Navier-Stokes equations, while the sediment concentration is calculated by an advection-diffusion equation for the conservation of sediment mass. The fluid turbulence is calculated by k f -ε f equations that incorporate the essential influence of sediment, which can also be consistently deduced from the two-phase theory. By adopting a commonly used sediment flux boundary condition near the bed the proposed models are tested against laboratory measurements of suspended sediment under nonbreaking skewed water waves and shoaling broken waves. Although the models predict wave-averaged sediment concentrations reasonably well, the corresponding time histories of instantaneous sediment concentration are less accurate. We demonstrate that this is due to the uncertainties in the near-bed sediment boundary conditions. In addition, we show that under breaking waves the near-bed sediment pickup cannot be solely parameterized by the bottom friction, suggesting that other effects may also influence the near-bed sediment boundary conditions.
Author Posting. © American Geophysical Union, 2004. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research 109 (2004): C06018, doi:10.1029/2003JC002240.
Suggested CitationArticle: Hsu, Tian-Jian, Liu, Philip L.-F., "Toward modeling turbulent suspension of sand in the nearshore", Journal of Geophysical Research 109 (2004): C06018, DOI:10.1029/2003JC002240, https://hdl.handle.net/1912/3583
Showing items related by title, author, creator and subject.
Eddy interaction model for turbulent suspension in Reynolds-averaged Euler-Lagrange simulations of steady sheet flow Cheng, Zhen; Chauchat, Julien; Hsu, Tian-Jian; Calantoni, Joseph (2017-10-31)A Reynolds-averaged Euler–Lagrange sediment transport model (CFDEM-EIM) was developed for steady sheet flow, where the inter-granular interactions were resolved and the flow turbulence was modeled with a low Reynolds number ...
Traykovski, Peter A.; Trowbridge, John H.; Kineke, Gail (John Wiley & Sons, 2015-03-19)Field observations from the spring of 2008 on the Louisiana shelf were used to elucidate the mechanisms of wave energy dissipation over a muddy seafloor. After a period of high discharge from the Atchafalaya River, acoustic ...
Remote acoustic monitoring of natural suspensate distributions, active suspensate resuspension, and slope/shelf water intrusions Orr, Marshall H.; Hess, Frederick R. (Woods Hole Oceanographic Institution, 1978-10)Acoustic data, transmissometer data, and calculations are presented which indicate that high-frequency acoustic backscattering systems can become a valuable tool in the remote monitoring of suspended particle distributions ...