Cohesive Sediment Transport Model Research Articles

Modelling of hydrodynamics and cohesive sediment transport in Tanshui River estuarine system, Taiwan

A laterally averaged two-dimensional numerical model is used to simulate hydrodynamics and cohesive sediment transport in the Tanshui River estuarine system. The model handles tributaries as well as the main stem of the estuarine system. Observed time series of salinity data and tidally averaged salinity distributions have been compared with model results to calibrate the turbulent diffusion coefficients. The overall model verification is achieved with comparisons of residual currents and salinity distribution. The model reproduces the prototype water surface elevation, currents and salinity distributions. Comparisons of the suspended cohesive sediment concentrations calculated by the numerical model and the field data at various stations show good agreement. The validated model is applied to investigate the tidally averaged salinity distributions, residual circulation and suspended sediment concentration under low flow conditions in the Tanshui River estuarine system. The model results show that the limit of salt intrusion in the mainstem estuary is located at Hsin-Hai bridge in Tahan Stream, 26 km from the River mouth under Q 75 flow. The null point is located at the head of salt intrusion, using 1 ppt isohaline as an indicator. The tidally averaged sediment concentration distribution exhibits a local maximum around the null point.

Three‐dimensional modelling of cohesive sediment transport in the Loire estuary

In the framework of a European research programme, processes describing cohesive sediment transport, including fluid mud movements and consolidation, have been modelled and implemented in the three-dimensional finite element model TELEMAC-3D, which solves free surface flow problems. The model has been applied to several European estuaries and among them, the Loire estuary in France. This application proved the ability of the code to reproduce typical estuarine features such as the formation of a turbidity maximum and the movements of fluid mud. Copyright © 2000 John Wiley & Sons, Ltd.

Three‐dimensional modelling of cohesive sediment transport in the Loire estuary

In the framework of a European research programme, processes describing cohesive sediment transport, including fluid mud movements and consolidation, have been modelled and implemented in the three-dimensional finite element model TELEMAC-3D, which solves free surface flow problems. The model has been applied to several European estuaries and among them, the Loire estuary in France. This application proved the ability of the code to reproduce typical estuarine features such as the formation of a turbidity maximum and the movements of fluid mud. Copyright © 2000 John Wiley & Sons, Ltd.

Three-dimensional modelling of cohesive sediment transport in the Loire estuary

Three-dimensional modelling of cohesive sediment transport in the Loire estuary

3D-numerical modelling of cohesive suspended sediment in the Western Scheldt estuary (The Netherlands)

A cohesive sediment transport model considering the effects of flocculation, deposition and erosion is used in an attempt to simulate the suspended sediment distribution in a mesotidal estuary. The numerical model solves the three-dimensional (3D) advection-diffusion equation using a two-time level scheme, and a semi-implicit finite difference approach. The transport model is coupled to a 3D-barotropic hydrodynamic model for the simulation of the major tidal components reproducing the non-linear effects. An application of these models in the Western Scheldt estuary is described. The results of the different tests show that the adopted approach provides a useful basis for a good understanding of the physical processes involved in sediment transport and for the study of practical problems. The sensitivity of the model to key parameters controlling the simulation of bed sediment/water exchanges, shows the importance of a good definition of bottom sediment characteristics and the importance of further development of a consolidation algorithm.

Modélisation du transport dissous et particulaire dans l'estuaire de Morlaix. Application au devenir des bactéries entériques

Modelling dissolved and particulate contaminants transport in the Morlaix estuary. Application to enteric bacteria discharge. Dissolved contaminants and cohesive sediment transport models have been developped and applied to a macrotidal estuary. These models are original as several dissolved and particulate constituents can be simultaneously computed, the later being followed in the surficial sediment according to the deposition events. Resides laboratory and field experiments have been conducted in order to evaluate the survival of enteric bacteria both within the sediment and the water body. Showing off rather long survival times especially in the sediment, the results have been introduced in the models in order to simulate the impact of urban disposal on water quality in a shellfishing area.

Modelling cohesive sediment transport in estuarial waters

Cohesive sediment related problems in estuaries include shoaling in navigable waterways and water pollution. A two-dimensional, depth-averaged, finite element (FE) cohesive sediment transport model, CSTM-H, has been developed and may be used to assist in predicting the frequency and quantity of dredging required to maintain navigable depths and the fate of adsorbed pollutants. Algorithms which describe the processes of erosion, dispersive transport, deposition, bed formation and bed consolidation are incorporated in CSTM-H. The Galerkin weighted residual method is used to solve the advection-dispersion equation with appropriate source/sink terms at each time step for the nodal suspended sediment concentrations. The model yields stable and converging solutions. Partial verification was carried out against a series of erosion-deposition experiments in the laboratory using kaolinite and a natural mud as sediment. Model applications under prototype conditions are described.

MODELING ESTUARIAL COHESIVE SEDIMENT TRANSPORT

Cohesive sediment related problems in estuaries include shoaling in navigable waterways and water pollution. A two-dimensional, depth averaged, finite element cohesive sediment transport model, CSTM-H, has been developed and may be used to assist in predicting the fate of sorbed pollutants and the frequency and quantity of dredging required to maintain navigable depths. Algorithms which describe the transport processes of redispersion, resuspenslon, dispersive transport, settling, deposition, bed formation and bed consolidation are incorporated in CSTM-H. The Galerkin weighted residual method is used to solve the advection-dispersion equation with appropriate source/sink terms at each time step for the nodal suspended sediment concentrations. The model yields stable and converging solutions. Verification was carried out against a series of erosion-deposition experiments in the laboratory using kaolinite and a natural mud as sediment. A model application under prototype conditions is described.

Closure to “Finite Element Model for Cohesive Sediment Transport”

Closure to “Finite Element Model for Cohesive Sediment Transport”