How is the Maximum Link Flow Applied in SWMM 5?

Subject:  How is the Maximum Link Flow Applied in SWMM 5?

How is the Maximum Link Flow Applied in SWMM 5?

by dickinsonre
Subject:  How is the Maximum Link Flow Applied in SWMM 5?
The maximum flow limit for a link applies to the kinematic wave and the dynamic wave solution.   The inflow to the link  in the kinematic wave solution is limited (Figure 1) but the calculated link flow is limited in the dynamic wave solution after the link flow (Figure 2):
1.       Is checked using the Culvert Inlet Equations (optional)
2.      The normal flow equation is checked (internally optional depending on the Normal flow options) and
3.      The Picard iteration solution under relaxation parameter (always 0.5) is applied (Figure 3).
Figure 1.  Kinematic Wave Solution Limits the Inflow to  the Link Maximum limit.
Figure 2. Dynamic Wave Solution link  flow limit.
Figure 3.  The Link  flow in the dynamic wave solution has three checks at each iteration in a time step.

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