The 2D shallow water equations in AdH are used to model open channel flow environments such as rivers, estuaries, reservoirs, and coastal regions. AdH in 2D calculates variables such as velocity, depth, and concentrations that describe their distribution in the horizontal plane. That is, say, in the x-y coordinate system. In the vertical direction, parameters such as concentration and velocity have an assumed vertical distribution. This often makes the 2D model sufficient for many rivers. However, in the case of estuaries or reservoirs one needs to be sure that stratification due to temperature or salinity doesn't invalidate this assumption. The 2D shallow water module of AdH utilizes the assumption that pressure is hydrostatic and that the bed slopes are mild. This is a typical assumption made in models of this type.
AdH in 2D can simulate flow as well as sediment transport and bed morphology. Both cohesive (clays) and noncohesive (sands and gravels) may be represented. Additionally, AdH includes a correction for the 3D effects of a bendway upon flow and sediment transport. With this correction, the 2D model can be used to reasonably characterize meandering rivers.
AdH in 2D is calculated on an unstructured mesh composed of triangular elements. AdH can adapt by refining or unrefining the mesh based upon user-defined parameters. Adaption generates an accurate result while using the least computational effort necessary. The publically released version of AdH will run on the PC for a single processor. It may also be compiled and run efficiently on multiprocessor PCs, Macs, Linux and Unix multiprocessor computers.