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When using a flow control valve (FCV) to regulate flow in the system downstream of a pump station there are negative pressures in many nodes or the model is unbalanced/unstable.Problem ID#: 67804
There could be multiple issues here:1) The FCV's could be limiting the demand to a number lower than the total of the fixed demands you have in your model. If you add up the flow settings for all the FCV's that are active in your model they should be equal to or greater than the total fixed demand on the nodes in your model.2) Sometimes if the FCV's are providing right around the same flow as is demanded from the model the calculation engine can have trouble mathematically converging. Slightly increasing the flow in the FCV's may help or if the demands in the model are actually pressure dependent demands then setting up a pressure dependent demand function might also help.If you still have issues after reading this and examining the data input for you model please contact technical support for more help.
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