Using the Link Geometry to Divide the Flow

You can use the geometry of the connecting pipes to divide the flow instead of flow divider in the dynamic wave solution of SWMM 5. You can try to do the same using an Outlet link but the method of using two outlets is sometimes very unstable and requires a small time step just to lower the continuity error. I used two flat rectangular links with the same maximum depth and but different width values (Figure 1). The flow was split based on the value of Q full for the link (which you can see in the text output file (Figure 2).

Figure 1. Link Geometry



Figure 2. Flow Division from a inflow of 10 mgd



Figure 3. SWMM 5.0.016 Cross section geometry for the two rectangular links.

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