The Three Flows in SWMM 5 for a Link
The Three Flows in SWMM 5 for a Link There are actually three flows computed or used for a link in SWMM 5 : 1. The St. Venant Flow equation flow 2. The Upstream Normal Flow Manning's equation based on the link roughness, slope, upstream cross sectional area and upstream hydraulic Radius, 3. The flow actually used in the model which is either the flow computed from St. Venant or Manning's equation The following three links shows how this works in a real model: · Link 8040 almost always uses the St. Venant Equation because it is dominated by backwater and surcharge · Link 8100 almost always uses Manning's equation except at the beginning and end of the simulation, · ...