Hello -
I am using StormCAD v8i....
We have a box manhole/vault (7'x7') with a weir plate set internally to control the flow for hydromodification. The top of the weir plate is set about 3' above the inlet pipe's invert and has two orifices for low flows set at different elevations in the middle of the weir (see sketch below).
Any suggestions on how I can model this effectively in StormCAD?
Sir, There is not a direct way to add a weir and orifice to a manhole. We suggest that you run the model as is without adding anything to the manhole to see what the flow is through the manhole. You could then set up a weir/orifice place in the pond outlet structure dialog to find out what the headwater is for that flow. To get to this dialog, you would need to layout a pond outlet structure that can be deleted when done, by going to Tools > Layout > Other - Storm > Pond Outlet Structure. With the results, you would then set up a structure loss coefficient that gives you that much head drop through the manhole.
Terry FosterTechnical SupportHydraulics and Hydrology product lineBentley Systems, Inc.