A finite difference model of two-dimensional tidal flow in Tolo Harbor, Hong Kong

An unsteady finite difference mathematical model of depth-averaged two-dimensional (2-D) flow for Tolo Harbor in Hong Kong has been developed based upon the numerically generated boundary-fitted orthogonal curvilinear grid system and the grid “block” technique. The model overcomes the Courant-Friedrichs-Lewy (CFL) stability criterion constraint and can allow the specification of a flexible initial condition. The error bars and the root mean square (rms) errors between the computed and the measured data show that the present model reproduces the depth-averaged 2-D flow in Tolo Harbor reasonably, and the computational results agree with the available measured data. It could be found from the numerical simulation that the flow exchange or tidal flushing in the inner part of the Harbor and in the small side coves is quite limited.