An application of two-phase 1DV model in studying sedimentary processes on an erosional mudflat at Yangtze River Delta, China

Abstract

A two-phase flow model for predicting sedimentation processes under wave and current conditions is presented. The model is based on solving the one-dimensional continuity and momentum equations for both fluid and solid phases through water column (1DV). The standard mixing length model is modified to take into account the buoyancy effect due to the gradient of suspended sediments near the seabed. The model is applied to study sedimentation processes on an erosional mudflat in the Yangtze River Delta, China, and intra-tide variations of flow properties and mud concentration are predicted and compared with field measurements. It was found that it is necessary to include the wave-induced shear stress in determining sediment erosion and the existence of a fluid mud layer can significantly influence both the flow structure and the distribution of sediment concentration in the water column. The turbulence dissipation induced by the fluid mud layer has the effect of increasing the duration of re-suspension during the early stage of the ebb. The overall good agreement between measured data and model results demonstrates the capability of the model.

Keywords

two-phase flow / sedimentary process / mudflat / fluid mud / stratification effects

References

[1] Boulton S J, Robertson A H F, Ünlügenç U C (2006). Tectonic and sedimentary evolution of the Cenozoic Hatay Graben, Southern Turkey: a two-phase model for graben formation. Geol Soc Lond Spec Publ, 260(1): 613–634

[2] Callaghan D P, Bouma T J, Klaassen P, van der Wal D, Stive M J F, Herman P M J (2010). Hydrodynamic forcing on salt-marsh development: distinguishing the relative importance of waves and tidal flows. Estuar Coast Shelf Sci, 89(1): 73–88

[3] Chauchat J, Guillou S (2008). On turbulence closures for two-phase sediment-laden flow models. J Geophys Res, 113(C11): C11017

[4] Chauchat J, Guillou S (2013). A vertical one-dimensional two-phase flow model for sedimentation-consolidation of mud. In: Proceedings of Coastal Dynamics. Arcachon, France, 327–338

[5] Chauchat J, Guillou S, Pham Van Bang D, Dan Nguyen K (2013). Modelling sedimentation–consolidation in the framework of a one-dimensional two-phase flow model. J Hydraul Res, 51(3): 293– 305

[6] Cheng Z, Yu X, Hsu T J, Ozdemir C E, Balachandar S (2015). On the transport modes of fine sediment in the wave boundary layer due to resuspension/deposition: a turbulence-resolving numerical investigation. Journal of Geophysical Research: Oceans, 120(3): 1918–1936

[7] Davies A G (1993). Modelling the Vertical Distribution of Suspended Sediment in Combined Wave‐Current Flow. In: Prandle D, ed. Dynamics and Exchanges in Estuaries and the Coastal Zone. Coastal and Estuarine Studies, 40: 441–466

[8] Dong P, Zhang K (1999). Two-phase flow modelling of sediment motions in oscillatory sheet flow. Coast Eng, 36(2): 87–109

[9] Graham A L (1981). On the viscosity of suspensions of solid spheres. Appl Sci Res, 37(3‒4): 275–286

[10] Héquette A, Hemdane Y, Anthony E J (2008). Sediment transport under wave and current combined flows on a tide-dominated shoreface, northern coast of France. Mar Geol, 249(3‒4): 226–242

[11] Hill P S, Milligan T G, Geyer W R (2000). Controls on effective settling velocity of suspended sediment in the Eel River flood plume. Cont Shelf Res, 20(16): 2095–2111

[12] Hsu T J, Traykovski P A, Kineke G C (2007). On modeling boundary layer and gravity-driven fluid mud transport. J Geophys Res, 112(C4): C04011

[13] Kirwan M L, Murray A B (2007). A coupled geomorphic and ecological model of tidal marsh evolution. Proc Natl Acad Sci USA, 104(15): 6118–6122

[14] Kranenburg C (1998). Saturation concentrations of suspended fine sediment: computations with the Prandtl Mixing-Length model, Report No. 5- 98. TU Delft.

[15] Liang B C, Li H J, Lee D Y (2008). Bottom shear stress under wave-current interaction. Journal of Hydrodynamics, Ser B, 20(1): 88–95

[16] Liu X J, Gao S, Wang Y P (2015). Modeling the deposition system evolution of accreting tidal flats: a case study from the coastal plain of central Jiangsu, China. J Coast Res, 299: 107–118

[17] McAnally W H, Friedrichs C, Hamilton D, Hayter E, Shrestha P, Rodriguez H, Sheremet A, Teeter A (2007). Management of fluid mud in estuaries, bays, and lakes. I: present state of understanding on character and behavior. J Hydraul Eng, 133(1): 9–22

[18] Montserrat F, Suykerbuyk W, Al-Busaidi R, Bouma T J, van der Wal D, Herman P M J (2011). Effects of mud sedimentation on lugworm ecosystem engineering. J Sea Res, 65(1): 170–181

[19] Nguyen K D, Guillou S, Chauchat J, Barbry N (2009). A two-phase numerical model for suspended-sediment transport in estuaries. Adv Water Resour, 32(8): 1187–1196

[20] Shi B W, Yang S L, Wang Y P, Bouma T J, Zhu Q (2012). Relating accretion and erosion at an exposed tidal wetland to the bottom shear stress of combined current–wave action. Geomorphology, 138(1): 380–389

[21] Son M, Hsu T (2011). The effects of flocculation and bed erodibility on modeling cohesive sediment resuspension. J Geophys Res, 116(C3): C03021

[22] Soulsby R L, Clarke S (2005). Bed shear-stresses under combined waves and currents on smooth and rough beds, Report TR137. HR Wallingford

[23] Spearman J R, Manning A J, Whitehouse R J S (2011). The settling dynamics of flocculating mud and sand mixtures: part 2—numerical modelling. Ocean Dyn, 61(2‒3): 351–370

[24] Taki K (2000). Critical shear stress for cohesive sediment transport. In: McAnally W H, Mehta A J, eds. Coastal and Estuarine Fine Sediment Processes. Proceedings in Marine Science, 3:53–61

[25] Teisson C, Simonin O, Galland J, Laurence D (1992). Turbulence and mud sedimentation: a Reynolds stress model and a two-phase flow model. In: Proceedings of 23rd international conference on coastal engineering. Venice: ASCE, 2853–2866

[26] Thorn M F C (1981). Physical processes of siltation in tidal channels. In: Proceedings of Hydraulic Modelling applied to Maritime Engineering Problems. London: ICE, 47–55

[27] Toorman E (2000). Modelling of turbulence damping in sediment-laden flow. Part 2: Suspension capacity of uniform shear flows. MAST III COSINUS Project Report(HYD/ET/00/COSINUS4)

[28] Toorman E, Bruens A, Kranenburg C, Winterwerp J (2002). Interaction of suspended cohesive sediment and turbulence. In: Winterwerp J C, Kranenburg C, eds. Fine Sediment Dynamics in the Marine Environment. Proceedings in Marine Science, 5: 7–23

[29] Torres-Freyermuth A, Hsu T J (2010). On the dynamics of wave-mud interaction: a numerical study. J Geophys Res, 115(C7): C07014

[30] van der Ham R, Winterwerp J C (2001). Turbulent exchange of fine sediments in a tidal channel in the Ems/Dollard estuary. Part II. Analysis with a 1DV numerical model. Cont Shelf Res, 21(15): 1629–1647

[31] Van L A (2013). Modélisation du transport des sédiments mixtes sable-vase et application à la morphodynamique de l’estuaire de la Gironde. Paris: University Paris-est

[32] Villaret C, Davies A (1995). Modeling sediment-turbulent flow interactions. Appl Mech Rev, 48(9): 601–609

[33] Wang Y, Gao S, Jia J (2006). High-resolution data collection for analysis of sediment dynamic processes associated with combined current-wave action over intertidal flats. Chin Sci Bull, 51(7): 866–877

[34] Winterwerp J C (2001). Stratification effects by cohesive and noncohesive sediment. J Geophys Res, 106(C10): 22559–22574

[35] Winterwerp J C (2006). Stratification effects by fine suspended sediment at low, medium, and very high concentrations. J Geophys Res, 111(C5): C05012

[36] Yang S L, Friedrichs C T, Shi Z, Ding P X, Zhu J, Zhao Q Y (2003). Morphological response of tidal marshes, flats and channels of the outer Yangtze River mouth to a major storm. Estuaries, 26(6): 1416–1425

[37] Zhu Q, Yang S, Ma Y (2014). Intra-tidal sedimentary processes associated with combined wave-current action on an exposed, erosional mudflat, southeastern Yangtze River Delta, China. Mar Geol, 347: 95–106

Acknowledgments

This work is supported jointly by the University of Dundee and the Chinese Scholarship Council through a PhD scholarship to CYX. We are also indebted to Prof Shilun Yang of East China Normal University for kindly making available the field data used in this study.

RIGHTS & PERMISSIONS

2016 Higher Education Press and Springer-Verlag Berlin Heidelberg