A WDM METHOD ON A GENERALIZED CURVILINEAR GRID FOR CALCULATION OF STORM-SURGE FLOODING

In this paper, the wet-dry grid point method (WDM) with generalized cu rvilinear computation grids is introduced with the aim of presenting a kind of effective numerical model for real-time forecasting of storm surge flooding. To realize this general WDM method, generalized 2-D sh allow sea dynamic equations in curvilinear co-ordinates are derived, a nd the contravariant components of the velocity vector are employed fo r easily realizing boundary conditions and making the wet-dry point ju dgement criterion more reasonable. As the generalized equations are no t limited to a specific co-ordinate transformation, a self-adaptive gr id generation method, which optimizes simultaneously grid smoothness, orthogonality and variation in cell volumes, is then proposed to meet the needs of WDM with varying spacing grids. The paper also provides a numerically stable difference scheme and this scheme is proved accura te by the verification calculation of observed storm surge. (C) 1998 E lsevier Science Limited. All rights reserved.