Development and validation of a three-dimensional morphodynamic modelling system for non-cohesive sediments

Abstract The morphology of estuaries and rivers changes constantly due to the dynamic imbalance between the forcing actions (e.g. river flow, tides, surface waves and wind) and the sedimentary reactions. Understanding and predicting these changes are very important for an scientific-based, sustained management of these systems. Morphodynamic process-based numerical models can be used for this purpose. The development and validation of a new three-dimensional unstructured grid morphodynamic modelling system, MORSELFE, aiming at simulating short-term morphological evolutions of estuaries and sandy rivers (temporal scale of days to month), are presented. MORSELFE couples a three-dimensional hydrodynamic model, with an advection–diffusion transport model for the suspended sediments, an empirical formula for the bed load, and a bed updating module. The model considers the simulation of non-cohesive sediment and does not account for wave effects. A new approach is proposed to compute the erosive fluxes, which adapts them to the vertical grid resolution. The use of unstructured grids and the implementation in parallel mode make MORSELFE particularly adapted to engineering applications. The model was assessed and validated against analytical and experimental test cases, also allowing the inference on the optimum choice of the model parameters and variables.

[1]  H. Burchard,et al.  A generic length-scale equation for geophysical turbulence models , 2003 .

[2]  D. Haidvogel,et al.  A semi-implicit ocean circulation model using a generalized topography-following coordinate system , 1994 .

[3]  L. Rijn,et al.  Mathematical modelling of morphological processes in the case of suspended sediment transport , 1987 .

[4]  P. Sweby.  High Resolution Schemes Using Flux Limiters for Hyperbolic Conservation Laws , 1984 .

[5]  Vincenzo Casulli,et al.  High resolution methods for multidimensional advection diffusion problems in free-surface hydrodynamics , 2005 .

[6]  André B. Fortunato,et al.  Improving the Stability of a Morphodynamic Modeling System , 2007 .

[7]  S. R. McLean,et al.  Spatially averaged flow over a wavy surface , 1977 .

[8]  J. McWilliams,et al.  Sediment-transport modeling on Southern Californian shelves: A ROMS case study , 2007 .

[9]  J. Damgaard,et al.  BED-LOAD SEDIMENT TRANSPORT ON STEEP LONGITUDINAL SLOPES , 1997 .

[10]  Syunsuke Ikeda,et al.  Lateral Bed Load Transport on Side Slopes , 1982 .

[11]  G. Mellor,et al.  Development of a turbulence closure model for geophysical fluid problems , 1982 .

[12]  André B. Fortunato,et al.  A modeling system for tidally driven long-term morphodynamics , 2004 .

[13]  H. K. Wong,et al.  Electron cyclotron wave generation by relativistic electrons , 1994 .

[14]  P. Woodward,et al.  The Piecewise Parabolic Method (PPM) for Gas Dynamical Simulations , 1984 .

[15]  R. Whitehouse.  Observations of the boundary layer characteristics and the suspension of sand at a tidal site , 1995 .

[16]  X. Bertin,et al.  A modeling-based analysis of processes driving wave-dominated inlets , 2009 .

[17]  Ida Brøker,et al.  Intercomparison of coastal area morphodynamic models , 1997 .

[18]  L. Rijn.  Principles of sediment transport in rivers, estuaries and coastal seas , 1993 .

[19]  R. Bagnold.  An approach to the sediment transport problem from general physics , 1966 .

[20]  S. Osher,et al.  Weighted essentially non-oscillatory schemes , 1994 .

[21]  M. Noble,et al.  Suspended sediment transport on the continental shelf near Davenport, California , 2002 .

[22]  A. Cucco,et al.  Modelling fluxes of water and sediment between Venice Lagoon and the sea , 2010 .

[23]  D. Wilcox.  Reassessment of the scale-determining equation for advanced turbulence models , 1988 .

[24]  Jørgen Fredsøe,et al.  Data analysis of bed concentration of suspended sediment , 1994 .

[25]  José Simão Antunes do Carmo.  Contribuição para o estudo dos processos morfodinâmicos em regiões costeiras e estuarinas , 1995 .

[26]  Kandiah Arulanandan,et al.  Erosion Rates of Cohesive Soils , 1978 .

[27]  John C. Warner,et al.  Performance of four turbulence closure models implemented using a generic length scale method , 2005 .

[28]  John C. Warner,et al.  Development of a three-dimensional, regional, coupled wave, current, and sediment-transport model , 2008, Comput. Geosci..

[29]  F. Cayocca,et al.  Long-term morphological modeling of a tidal inlet: the Arcachon Basin, France , 2001 .

[30]  André B. Fortunato,et al.  MASS BALANCE IN EULERIAN-LAGRANGIAN TRANSPORT SIMULATIONS IN ESTUARIES , 2000 .

[31]  C. Briere,et al.  Assessment of TELEMAC system performances, a hydrodynamic case study of Anglet, France , 2007 .

[32]  Wolfgang Rodi,et al.  Modeling Suspended Sediment Transport in Nonequilibrium Situations , 1988 .

[33]  M. S. Dubovikov,et al.  Ocean Turbulence I: One-Point Closure Model Momentum and Heat Vertical Diffusivities , 2001 .

[34]  Edward P. Myers,et al.  A cross-scale model for 3D baroclinic circulation in estuary-plume-shelf systems: I , 2004 .

[35]  R. Soulsby.  Dynamics of marine sands : a manual for practical applications , 1997 .

[36]  Jørgen Fredsøe,et al.  A Sediment Transport Model for Straight Alluvial Channels , 1976 .

[37]  Marcelo Horacio Garcia,et al.  Entrainment of Bed Sediment into Suspension , 1991 .

[38]  R. Müller,et al.  Formulas for Bed-Load transport , 1948 .

[39]  L. Rijn.  Unified view of sediment transport by currents and waves. I: Initiation of motion, bed roughness, and bed-load transport , 2007 .

[40]  André B. Fortunato,et al.  Simulating morphodynamics with unstructured grids: Description and validation of a modeling system for coastal applications , 2009 .

[41]  J. Ribberink,et al.  Quasi-3D modelling of suspended sediment transport by currents and waves , 1992 .

[42]  Alan F. Blumberg,et al.  Modeling Vertical Structure of Open-Channel Flows , 1992 .

[43]  Patricia L. Wiberg,et al.  A two-dimensional, time-dependent model of suspended sediment transport and bed reworking for continental shelves , 2001 .

[44]  A. Rosati,et al.  A Quasi-equilibrium Turbulent Energy Model for Geophysical Flows , 1988 .

[45]  R. Soulsby,et al.  Threshold of Sediment Motion in Coastal Environments , 1997 .

[46]  P. Wiberg,et al.  Wind-driven sediment suspension controls light availability in a shallow coastal lagoon , 2007 .

[47]  H. Einstein,et al.  The Bed-Load Function for Sediment Transportation in Open Channel Flows , 1950 .

[48]  António M. Baptista,et al.  SELFE: A semi-implicit Eulerian–Lagrangian finite-element model for cross-scale ocean circulation , 2008 .

[49]  L. Kantha,et al.  An improved mixed layer model for geophysical applications , 1994 .

[50]  Zhixian Cao,et al.  EQUILIBRIUM NEAR-BED CONCENTRATION OF SUSPENDED SEDIMENT , 1999 .

[51]  Dirk-Jan R. Walstra,et al.  Evaluation of coastal area modelling systems at an estuary mouth , 2004 .

[52]  L. Rijn.  Sediment Transport, Part II: Suspended Load Transport , 1984 .

[53]  G. Stelling,et al.  Development and validation of a three-dimensional morphological model , 2004 .

[54]  P. Bradshaw,et al.  Turbulence Models and Their Application in Hydraulics. By W. RODI. International Association for Hydraulic Research, Delft, 1980. Paperback US $15. , 1983, Journal of Fluid Mechanics.