Is it possible to model a fixed flow VSP where the flow changes over time?

Product(s): WaterGEMS, WaterCAD, SewerCAD
Version(s): CONNECT Edition V8i
Area: Modeling

Problem

Is it possible to model a fixed flow variable speed pump where the flow changes over time? For example a logical control to change the target flow.

Solution

As of version 10.03.02.75,  there is currently not a direct way of doing this at this time due to technical reasons (although target pressure and target HGL for fixed head VSPs is available). There are a few options that are available to you. First, you could model this as a pattern-based variable speed pump instead. This would require trial and error to determine the pump speed that results in the desired fixed flow.

A simpler solution would be to omit the pump altogether and model the flow from the pump as an inflow node. This is basically using a junction with a negative demand. The negative demand can follow a pattern, which would allow you to control the flow going into the system.

We will investigate including target flow as an available control action for a future release. Reference Enhancement # 782645

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