Dynamics of wave-supported gravity currents in intermediate water

The dynamics of gravity currents propagating beneath intermediate water waves is investigated in the present study. Laboratory experiments were carried out in a wave flume, in which saltwater was released into freshwater by means of a point-release setup in the presence of a fully developed wave field. Results revealed a series of interesting...

Assessing the Effectiveness of the IJmuiden Salt Screen Design for Nonuniform Selective Withdrawal by Physical and Numerical Modeling

Salt water intrusion through the New Sea Lock of IJmuiden, Netherlands requires mitigation to ensure availability of enough fresh water further inland. For this purpose, a salt screen has been proposed for selective withdrawal of salt water from the Noordzeekanaal in the vicinity of the lock complex. Formulas to assess the withdrawal rate of...

Channelling Turbid Density Currents in Dam Reservoirs

Dam reservoirs form a crucial part for human society storing water, controlling floods, providing hydropower, water for irrigation and drinking. Annually 1% of the worldwide dam reservoirs storage capacity is lost, caused by sedimentation. The inflow of sediment and reduction of flow velocity and turbulence in the reservoir pro- vides favourable...

Turbidity Currents in Reservoirs

Turbidity currents are major transport agents in reservoirs in which high concentrations of fine sediments flow in. Reservoir sedimentation due to turbidity currents is often severe in these cases. Turbidity currents are not well understood due to their complex turbulent flow structure, the interaction between the flow with the particles and the...

Near-field verspreiding van het overvloeiverlies van een sleephopperzuiger

In opdracht van Directie Noordzee is onderzoek gedaan naar de verspreiding van het overvloeiverlies bij sleephopperzuigers. Dit onderzoek is gericht op de vraag: wanneer treedt er menging van het overvloeiverlies met de waterkolom op en wanneer gedraagt het overvloeiverlies zich a1s een dichtheidsstroom. In geval van een dichtheidsstroom komt...

Spatial and temporal variability of the Ba Lat River plume

Survey of data regarding the sediment plume of the Ba Lat river (branch of the Red River, Vietnam). Data collected in 2000. Contains detailed datasets. [blz 2 van dit rapport ontbreekt.]

Waterinjectiebaggeren: Modellering van de afstroming

In 1984 en 1985 hebben proeven aangetoond dat het mogelijk is om dichtheidsstromen op te wekken van water met een hoog sedimentgehalte. Het onder lage druk (ca. 1 bar) injecteren van water in de bodem, het zogenaamde 'jetten' verdunt de bodem tot een water-sedimentmengsel. Door het verschil in dichtheid tussen het water-sedimentmengsel en het...

Salinity in Lake Maracaibo

Lake Maracaibo, Venezuela is an outstanding example of today's conflict of interests between protection of natural resources and economic development because of the extensive use of the area. The exchange and interaction between the fresh water of the Lake and the saline water from the Gulf of Venezuela is an important mechanism in the...

Density currents and salt intrusion

Lecture notes for IHE

International Conference on Physical Modeling of Transport and Dispersion

Proceedings of the 4th conference organized by IAHR (section on experimental methods and physical modeling) on scale effects. Special keynotes and invited presentations describe the contributions of Dr. Keulegan and their relation to present work in mixing processes, stratified flow and other areas of fluid mechanics. These proceedings contain...

Density currents and siltation - with particular reference to Cochin -

In an estuary, the confluence of fresh water of upland rivers with salt water from the sea gives rise to a complex regime of flow pattern due to the difference in densities of the two liquids of about 2.5%. Vhen the estuary is stratified, the heavier salt water which dives underneath the lighter fresh water extends as a long wedge far into the...

Salt intrusion in the river Maputo, Mozambique; field survey and one-dimensional modelling

The aim of the study was to give an indication of the accuracy and applicability of one-dimensional salt intrusion models in estuaries in Mozambique. Attention is mainly centered on tidally averaged modeis, although some preliminary testing of a real- time model is included as weIl. Testing of the models is done with data, obtained from a field...

One-dimensional analysis of salinity intrusion in estuaries

This report describes a mathematical model that was developed to predict salinity intrusion in estuaries as it is affected by control and abstraction of fresh water. The need for such a model, particularly for estuaries in tropical areas with large variations in fresh water flow, capable of giving satisfactory predictions of salinity movement...

Salt distribution in Estuaries

Seminar proceedings (1974): Density currents due to differences in salinity (G. Abraham) - Emperical methods of forecasting movement of salt in estuaries (F. Langeweg and J. J. van Weerden) - Mathematical investigation of stratified flow (C. B. Vreugdenhil) - The use of hydraulic models for the study of salt-fresh water currents in aid of...

Introduction to Coastal Engineering and Breakwaters

Collegedictaat f11a and f11b. Lecture notes, short waves, waves near shoreline, coastal formation, sediment transport by waves, coastal protection, delta coasts, muddy coasts, tidal rivers, density currents, breakwater design.

Computation of gravity currents in estuaries

A great deal of literature has been devoted to gravity currents in estuaries. However, more or less detailed theoretical models of these phenomena are scarce. This is partly due to the fact that the equations have been difficult to solve if they describe the situation with some generality. This difficulty is surmounted by the use of digital...

Theoretical considerations on the motion of salt and fresh water

This paper gives a survey of the theoretical investigations in Holland on the motion of salt and fresh water in estuaries, locks, etc. The insight gained is set forth, and also questions yet unsolved are mentioned. First the long wave phenomena in the interface of two sharply separated liquids are treated, and in connection herewith, the cases...