Research on a Mathematical Model of Storm Surge and Inundation in Bohai Bay

Abstract

A two-dimensional extratropical storm surge and inundation numerical model was built based on the unsteady flow N-S equations. This model was divided into two sections, one is the simulation of storm surge tidal level and the other is the simulation of storm surge inundation on the coastal area. While simulating the storm surge tidal level, the FDM (finite difference method) was applied for dispersing and solving the 2D storm surge equations using the ADI (Alternating Direction Implicit) difference scheme. In the simulation of storm surge inundation, the 2D unsteady flow equation was dispersed and solved using the structureless mesh method of FVM (finite volume method). The calculation mode that connecting the process of storm surge floodplain with the process of storm surge tidal level variation was also introduced in this paper, therefore the storm surge floodplain process and area can be calculated while simulating and forecasting the process of storm surge tidal level setup. Furthermore, an extratropical storm surge which happened in Bohai Bay was simulated and validated using this numerical model, and the process of storm surge floodplain on the coastal area was also simulated. Data comparisons reveal that this model’s calculation results are in good agreement with the measured results, which showed that this numerical model provides a new method of simulating and forecasting for storm surge and inundation in Bohai Bay.