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ProbSolver352
January 30, 2017, 04:32 PM
I have a system that has 6 pumps drawing from 6 different reservoirs and I want to generate a total system curve, but when I go to the run for a system curve it makes me pick a specific pump. Does anyone know how to generate a total system curve for all the running pumps in InfoWater?

Patrick Moore
January 30, 2017, 05:17 PM
David,

A true system curve is generated for the entire pump station and reflects the energy needed to push water into the system from that pump station.

In order to make the tool useable, it asks a user to identify a single pump and uses it to generate a system curve. The max flow however is based on the pump curve assigned to that pump where that pump curve would have zero head. This will also use the pipes connected to that pump as well. This as you have noted may not create the full flow range for the facilities system curve as desired. To get around this it is often easiest to create a new dummy pump that is connected to the main suction node and main discharge node of the station and contains a combined pump curve representing all 6 pumps (note to do this if all pumps are the same size is you keep the head constant and add all the flow values at a given head together to get the combined pump curve when all 6 pumps are running.

Now, since you have 6 reservoirs (one for each pump (Not sure exactly why this is the case unless each pump is of a different size and/or each pump has a different suction head) this may be a bit trickier. As long as the suction head values are similar, then you can connect your dummy pump to any one reservoir and it should be sufficient. If it is not, please contact us at support@innovyze.com and refer to this forum thread and we can discuss that one further as it has some complicating factors.

We have created a presentation to explain many of the features of system curves that should help further your understanding. You can download it here: http://innovyze.com/files/2017/InfoWater_System_Curve_Basics_v1.4.pdf

This describes many key things you should consider when creating system curves using a hydraulic model. Please download that and if you still have remaining questions please either reply to this post or send us an email at support@innovyze.com.

Patrick Moore