This discussion has been locked.
You can no longer post new replies to this discussion. If you have a question you can start a new discussion

PondPack V8i - Orifices in series??

Can PondPack model orifices in series?  I have a scenario where I have an existing 7" orifice plate mounted to an 18" culvert to control the outflow from a detention basin.  I now need to restrict the flow for a 1-yr event even more with a 4" orifice at the pond discharge elevation (46.86ft).  I want to allow all events more than a 1-yr to use the existing 18" culvert, so I put in a weir at an elevation slightly above the 1-yr water surface (50.25ft).  All water overtopping this weir can then re-enter the 18" culvert.  Somewhere I need to still control the release with a 7" orifice plate.  I have tried modeling the 7" orifice plate at two different spots: at the pond discharge, and at the downstream pipe of the outlet structure containing the weir.

The attached image shows what I would like to model.  PondPack enters some endless loop when analyzing this outlet structure.  It seems that when I enter two orifices in my outlet structure they both are draining the pond simultaneously (in parallel) rather than in series where one orifice's discharge would then go through the other orifice.

 Any suggestions on how to model this situation?