Research On Three-dimensional Numerical Model For Storm Surge And Its Application

The analyses and investigations indicate that the Bohai bay is one of the areas where the frequency of storm surge is the highest and most severe in the world, and the disaster of extratropical storm surge occurs in spring, autumn and winter. The two-dimensional storm surge has been studied a lot, but the research on three-dimensional storm surge has broader development space.The former stressed the forecast of anstau before or after the storm, the latter has more application in the construction of key project such as offshore oil platform, sea floor pipeline, etc. In fact, these projects are more concerned the impact of storm surge on the life and safety of the projects in extreme weather conditions.Based on the numerical model of two-dimensional extratropical storm surge of lab oratory,the text deduces systematically the three-dimensional storm surge governing equation,makes use of explicit-implicit alternating finite difference,namely ADI (Alternating Direction Implicit Method) method,discretize the three-dimensional governing equation,uses chasing method to solve the discrete equation, establishes the big model of whole range and the small model of Local range,uses harmonic analysis to give the open tidal boundaries of big model,then uses the calculated results of big model to give the open tidal boundaries of small model,computes the astronomical process of Bohai bay, verifies the harmonic analysis data of Qingdao, astronomical process of tanggu, the velocity and direction of flow of Chengbei,the calculated results are almost consistent with the measured data.In the calculation of storm surge, brings in the simulation results of MM5, simulate and forcast the flow and tidal process, then verifies it, the variation trend is basically uniform.The author compiles the core program of the three-dimensional storm surge, the auxiliary programs which are used to deal with the model data before and after the calculation and some other programs of Graphical User Interface. This test mainly simulates the course of storm surge which happened in May 2009 which last 72 hours, the calculated tide shows agreement with Tanggu actual tidal data in value and trend, it indicates that the model is reasonable and have valuable significance.