BOUNDARY-FITTED GRID MODELS FOR TIDAL MOTIONS IN SINGAPORE COASTAL WATERS

This paper describes the application of a 2-D nested model in rectangu lar coordinates and an orthogonal boundary fitted grid (BFG) model to tidal motions in Singapore coastal waters. The basic mathematical mode l for shallow water waves in the BFG model is derived from the transfo rmation of corresponding depth averaged equations in rectangular coord inates. The curvilinear coordinate system is obtained from the solutio n of a grid generator based on the elliptic generation technique. The BFG model is applied to the Singapore coastal region and its surroundi ng waters with a complicated domain and internal island groups. The ti dal flow behaviour including current circulation, time history of sea levels and currents as well as patterns of residual currents are inves tigated. The numerical results are successfully compared with the fiel d measurements.