Great Lakes River‐Estuary Hydrodynamic Finite Element Model

Abstract

A deterministic hydrodynamic model for simulating the water flow in a well‐mixed freshwater estuary is developed for the purpose of long‐term environmental flow simulation. The hydrodynamic simulation is based on solving the shallow‐water equations using the finite element method. The Galerkin approach to the finite element method is applied to approximate the spatial variables. A leapfrog scheme is used to evaluate the temporal terms of the unsteady‐state hydrodynamic equation. The combined numerical scheme has proven to be an efficient and conditionally stable method suitable for long‐term, real‐time simulation. The numerical method is verified with a set of analytical solutions for various geometric channel configurations. In addition, the model has been applied in the lower Green Bay and Fox River system in Lake Michigan using an extensive set of field data measured specifically for calibration and confirmation purposes.