Figure 1. Rectangular land-water grid supported by SSFATE, upper Narragansett Bay, Rhode Island

ERDC TN-DOER-E10

April 2000

three-dimensional (3-D) flow field generated by a numerical hydrodynamic model such as CH3D

(Curvilinear Hydrodynamics in 3 Dimensions) developed by Johnson et al. (1991).

As implied by these two options, two types of grids are allowed in SSFATE. If currents are painted,

the grid is rectangular with rectangular cells that are either land or water cells. Figure 1 shows an

example of such a grid generated for upper Narragansett Bay, Rhode Island.

Figure 1. Rectangular land-water grid supported by SSFATE, upper Narragansett Bay, Rhode Island

However, if 3-D hydrodynamics are imported, SSFATE supports either a rectangular or a boundary-

fitted curvilinear grid such as shown in Figure 2, again for the upper Narragansett Bay.

In addition to transport and dispersion, sediment particles also settle at some rate from the water

column. Settling of mixtures of particles, some of which may be cohesive in nature, is a complicated

process with the different size classes interacting; i.e., the settling of one particle type is not

independent of the other types. The procedure that has been implemented in SSFATE is described

in the following paragraphs, taken from Teeter (in review).