What is Link Bypass in SWMM 5?

Subject: What is Link Bypass in SWMM 5?
If a link has converged within two iterations then the hydraulic computations will be bypassed for new iterations. A link is deemed converged if BOTH the upstream and downstream nodes depth has converged between successive iterations as long as two iterations have occurred during the time step. This is simulation savings step as it my eliminate up to 75 percent of the computational time in a SWMM 5 simulation. The image below shows that for some links the flow in the link is converged within 2 iterations whereas for others it may take 3 or 4 iterations. Overall, 37 percent of the link computations are bypassed during the simulation of this particular hydraulic network.

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