MODELING COARSE SAND TRANSPORT UNDER SKEWED OSCILLATORY FLOW USING A CFD-DEM APPROACH

  • Yashar Rafati
  • Zhen Cheng
  • Xiao Yu
  • Tian-Jian Hsu
  • Joseph Calantoni

Abstract

Onshore/offshore sediment transport in the nearshore is an important mechanism driving the evolution of coastal morphology. The so-called sheet flow is a transport regime, in which the flow forces are intense such that a large amount of transport occurs in a concentrated layer near the bed. Onshore transport is often associated with flow skewness/asymmetry. In the nearshore zone, due to the bottom slope and wave shoaling, the wave velocity tends be onshore skewed before breaking in the surf zone. For breaking waves, the velocity asymmetry (or acceleration skewness) may also play a key role in determining net sediment transport. Understanding the net sediment transport rate in response to wave skewness/asymmetry is fundamental to a better prediction of sediment transport in regional scale morphodynamic models. In this study, we used an Euler-Lagrange two-phase model to study sheet flow transport of coarse sand under oscillatory flows subject to velocity/acceleration skewness.

References

Cheng, Hsu, Calantoni (2017): SedFoam: A multi-dimensional Eulerian two-phase model for sediment transport and its application to momentary bed failure, Coastal Engineering, pp. 32-50.

Cheng, Chauchat, Hsu, Calantoni (2018): Eddy interaction model for turbulent suspension in Reynolds-averaged Euler- Lagrange simulations of steady sheet flow, Advances Water Resources, vol. 111, pp. 435-451.

Cundall, Strack (1979): A discrete numerical model for granular assemblies, vol. 29(1), pp. 47-65.

Goniva, Kloss, Deen, Kuipers, Pirker (2012), Influence of rolling friction on single spout fluidized bed simulation, Particuology, vol. 10(5), pp. 582-591.

Graham, James (1996): Turbulent dispersion of particles using eddy interaction models, International Journal of Multiphase Flow, vol. 22(1), pp. 157-175.

O'Donoghue, Wright (2004): Concentration in oscillatory sheet flow for well sorted and graded sands, Coastal Engineering, vol. 50, pp.117-138.

van der A, Ribbrink, van der Werf, O'Donoghue (2013): Practical sand transport formula for non-breaking waves and currents, Coastal Engineering, vol. 76, pp. 26-42.

van Rijn (2007): Unified view of sediment transport by currents and waves, J. Hydraulic Eng., vol. 133(7), pp. 761-775.

Published
2018-12-30
How to Cite
Rafati, Y., Cheng, Z., Yu, X., Hsu, T.-J., & Calantoni, J. (2018). MODELING COARSE SAND TRANSPORT UNDER SKEWED OSCILLATORY FLOW USING A CFD-DEM APPROACH. Coastal Engineering Proceedings, 1(36), sediment.18. https://doi.org/10.9753/icce.v36.sediment.18

Most read articles by the same author(s)