Domain Decomposition for a Hybrid Fully 3D Fluid Dynamics and Geophysical Fluid Dynamics Modeling System: A Numerical Experiment on Transient Sill Flow

Abstract

A modeling system is presented for prediction of multiscale and multiphysics coastal ocean processes, and a numerical experiment is made to evaluate its performance. The system is a hybrid of a fully three dimensional fluid dynamics (F3DFD) model and a geophysical fluid dynamics (GFD) model. In particular, it integrates the Solver for Incompressible Flow on Overset Meshes (SIFOM) and the Finite Volume Coastal Ocean Model (FVCOM) using a domain decomposition method implemented with Chimera grids. In the hybrid SIFOM–FVCOM system, SIFOM is employed to capture small-scale local phenomena, and FVCOM is used to simulate large-scale background coastal flows. Simulation of a transient sill flow demonstrates that, while its performance is promising, the hybrid SIFOM–FVCOM system encounters difficulties in correctly resolving the flow at current front where there is strong unsteadiness and thus it needs further improvement.