A Bay/Estuary Model to Simulate Hydrodynamics and Water Quality Transport: Part 1 - Hydrodynamics

Abstract

This paper presents the development and application of a bay/estuary model to simulate hydrodynamics and thermal and salinity transport. The hydrodynamic module solves three-dimensional Navier-Stokes equations with or without the hydrostatic assumptions. The turbulence is modeled with typical transport equations. The Boussinesq approximation is employed to deal with the buoyancy force due to temperature and salinity variations. The moving free surface is explicitly handled by solving the kinematic boundary condition equation using a node-repositioning algorithm. The transport module solves the energy equation for spatial-temporal distributions of temperature and the mass transport equations for the salinity field. The Arbitrary Lagrangian-Eulerian (ALE) representation is adopted for all transport equations including momentum transport. The solution is obtained with finite element methods or a combination of finite element and Semi-Lagrangian (particle tracking) methods. The model has been successfully calibrated with tides and salinities and is applied to Loxahatchee Estuary for the investigation of its minimum flow requirements to maintain ecological balance.