Three-dimensional numerical simulation for tidal motion in Singapore's coastal waters

This paper describes the development and application of a three-dimensional (3-D) multi-level hydrodynamic model to tidal motions in Singapore's coastal waters. In this model, a two-step Euler predictor-corrector algorithm is introduced to predict and correct the free surface water elevation. The governing equations are explicitly and implicitly discretized into finite difference forms in a non-uniform staggered grid system. The velocity components in the x, y and z directions are directly obtained. The 3-D model is tested against analytical solutions for two standard cases in rectangular basins. The model results for the velocities and the free surface water elevations coincide with analytical results. The model is applied to the Singapore coastal region and its surrounding waters. In the first simulation, the tidal current behavior including current circulation, time history of sea levels, currents and discharges as well as patterns of residual currents without wind effects is predicted. The numerically predicted results show good agreement with field measurements. In the second simulation, the response of velocity fields to seasonal wind forcing is investigated. (C) 2000 Elsevier Science B.V. All rights reserved.