ICCE 2012 Cover Image


sediment transport
turbulence-resolving simulation
wave boundary later
fluid mud

How to Cite

Hsu, T.-J., Yu, X., Ozdemir, C. E., & Balachandar, S. (2012). A 3D NUMERICAL INVESTIGATION OF FINE SEDIMENT TRANSPORT IN AN OSCILLATORY CHANNEL. Coastal Engineering Proceedings, 1(33), sediment.9. https://doi.org/10.9753/icce.v33.sediment.9


Recent findings on a diverse range of muddy seabed states revealed by 3D, turbulence-resolving simulations are first reviewed. These transitions have critical implications to offshore delivery of fine sediment in the ocean and wave dissipation. Assuming a small particle Stokes number, the Equilibrium approximation to the Eulerian two-phase flow equations is applied. The resulting simplified equations are solved with a high-accuracy pseudo-spectral scheme in an idealized oscillatory bottom boundary layer (OBBL). For a typical energetic muddy shelf, the Stokes Reynolds number Reï,, is no more than 1000 and all of the scales of flow turbulence and their interaction with sediments are resolved. With increasing sediment availability or settling velocity, the seabed state evolves from well-mixed sediment distribution, to the formation of lutocline and a complete laminarization of the OBBL. More recently, we further include rheological stress in the simulations in order to study the interplay between turbulence and rheology in determining the flow regimes and hydrodynamic dissipation. To include rheological stress, we extend the numerical model with a hybrid spectral and compact finite difference scheme. A sixth-order compact finite difference is implemented in vertical direction to keep the spectral-like accuracy. The model is validated with analytical solutions using simple Newtonian rheology in laminar condition. Preliminary results at Reï¤=600 reveal that when rheology is incorporated, high viscosity can trigger earlier laminarization of OBBL. When OBBL is laminarized, sediments settle and higher concentration is accumulated near the bed that further enhances viscosity and hydrodynamic dissipation. Our preliminary finding that rheology encourages laminarization may explain why large attenuation of surface waves over muddy seabed is ubiquitous and the highest dissipation rate is often observed during the waning stage of a storm.


Balachandar, S., and J. K. Eaton 2010. Turbulent dispersed multiphase flow, Annu. Rev. Fluid Mech., 42, 111-133, doi:10.1146/annurev.fluid.010908. 165243.

Cantero, M.I., Lee, J.R., Balachandar, S., Garcia, M.H., 2007. On the front velocity of gravity currents. J. Fluid Mech. 586, 1-39.http://dx.doi.org/10.1017/S0022112007005769

Cantero, M.I., S. Balachandar, A. Cantelli, C. Pirmez, & G. Parker, 2009. Turbidity current with a roof: Direct numerical simulation of self-stratified turbulent channel flow driven by suspended sediment. J. Geophys. Res. 114, C03008.http://dx.doi.org/10.1029/2008JC004978

Cortese, T., Balachandar, S., 1995. High performance spectral simulation of turbulent flows in massively parallel machines with distributed memory. Int. J. Supercomput. Appl. 9 (3), 187-204.http://dx.doi.org/10.1177/109434209500900302

Einstein, A., 1906. Eine neue Bestimmung der Molekuldimensionen. Annln. Phys. 19, 298-306.

Ferry, J., Balachandar, S., 2001. A fast Eulerian method for disperse two phase flow. Int. J. Multiphase Flow 27, 1199.http://dx.doi.org/10.1016/S0301-9322(00)00069-0

Hill, P. S., T. G. Milligan, and W. R. Geyer 2000. Controls on effective settling velocity in the Eel River flood plume, Cont. Shelf Res., 20, 2095-2111, doi:10.1016/S0278-4343(00)00064-9.http://dx.doi.org/10.1016/S0278-4343(00)00064-9"

Hino, M., Sawamoto, M., Takasu, S., 1976. Experiments on transition to turbulence in an oscillatory pipe flow. J. Fluid Mech. 75, 193.http://dx.doi.org/10.1017/S0022112076000177

Hunt, J. C. R.,Wray, A. A. and Moin, P. 1988, Eddies, stream, and convergence zones in turbulent flows. Center for Turbulent Research Report CTR-S88, p. 193.

Lele, S. K., 1992. Compact Finite Difference Schemes with Spectral-like Resolution, J. Comput. Phys. 103, 16-42.http://dx.doi.org/10.1016/0021-9991(92)90324-R

Ozdemir, C. E., T.-J. Hsu, and S. Balachandar 2010. A numerical investigation of fine particle laden flow in oscillatory channel: The role of particle-induced density stratification, J. Fluid Mech., 665, 1-45, doi:10.1017/S0022112010003769.http://dx.doi.org/10.1017/S0022112010003769

Ozdemir, C. E., T.-J. Hsu, and S. Balachandar 2011. A numerical investigation of lutocline dynamics and saturation of fine sediment in the oscillatory boundary layer, J. Geophys. Res., 116, C09012, doi:10.1029/2011JC007185.http://dx.doi.org/10.1029/2011JC007185

Shukla, R. K. and X.-L. Zhong 2005, Derivation of high order compact finite difference schemes for non uniform grid using polynomial interpolation. J. Comput. Phys., 204 (2), 404-429.http://dx.doi.org/10.1016/j.jcp.2004.10.014

Traykovski, P., W. R. Geyer, J. D. Irish, and J. F. Lynch 2000. The role of wave-induced fluid mud flows for cross-shelf transport on the Eel river continental shelf, Cont. Shelf Res., 20, 2113-2140, doi:10.1016/S0278-4343(00)00071-6.http://dx.doi.org/10.1016/S0278-4343(00)00071-6

Authors retain copyright and grant the Proceedings right of first publication with the work simultaneously licensed under a Creative Commons Attribution License that allows others to share the work with an acknowledgement of the work's authorship and initial publication in this Proceedings.