Numerical Modelling Of Three-dimensional Non-Cohesive Sediment Transport In Java Sea

Abstract

In the framework of an integrated research project on prediction of beach and sea floor topography changes in Java Sea, the development of a three-dimensional non-cohesive sediment transport model to predict suspended sediment fluxes has been carried out by solving the advection-diffusion equation. The velocity fields were calculated by using a three-dimensional hydrodynamic model of tideand wind-driven circulation incorporating the influence of wind waves generated at the sea surface. The third generation wave model WAM (WAMDI ) was used to calculate the wave parameters and the wave dependence of the drag coefficient. To represent the monsoon wind fields which play an important role in generating the waves and water circulation in the region, ECMWF's one-year hindcasted data of six hourly-wind fields at 10 m above the sea surface were used in the simulation. The simulation results show that both for the typical westand east-monsoon the largest values of the suspended sediment concentration can be observed around central part of the Java Sea, where the velocities are largest. One-year computation of the bed level changes in the region produces erosion and deposition in the range 0 to 1.5 cm. Due to the most of the sea floor of the Java Sea being covered by mud (Emery et a//), the model will be extended to predict cohesive sediment transport. These kinds of studies are currently in progress as an extension of this research program. Transactions on the Built Environment vol 40 © 1999 WIT Press, www.witpress.com, ISSN 1743-3509