Author(s): Binliang Lin; Roger A. Falconer
Keywords: Rivers; Estuaries; Hydrodynamic predictions; Numerical models; Integrated models
Abstract: Numerical models based on solving the Navier-Stokes and solute transport equations have been widely used for predicting hydrodynamic and water quality processes in river, estuarine and coastal waters. For river and open channel problems these equations are often averaged over the cross-sectional area to give a set of one-dimensional (1-D) equations and numerical models developed based on solving these 1-D equations are called 1-D models. Similarly, for estuarine and coastal problems, depth-averaged two-dimensional (2-D) models have been developed and widely used. In many practical situations both one and two dimensional flows co-exist across different parts of the study area, thus both 1-D and 2-D models are generally used separately in these areas. Details are given herein of three methods developed for integrating 1-D and 2-D models for simulating the flow and solute transport processes in river and estuarine waters. With the first method a weir equation is used to connect the 1-D and 2- D model areas. With the second method an overlapping area is used to allow hydrodynamic and water quality information to be transferred between the 1-D and 2-D models. Finally, with the third method the 1-D equations are reformulated to enable them to be solved on one row, or column, of a 2-D grid. Each method was used for a specific hydrodynamic or water quality study, with the details of these applications being presented in the paper.