Pump flow

[Borys]

I am modeling pump with constant rate for a few months. For some reason chart for volume of tank water is pumped to has spikes. How I could remove this spikes. At the same time chart for volume of tank water is pumped from has change of volume as 0 for dry weather. Thanks

[Chris Maeder]

Note that I looked at your model, but since it contains an external rainfall file that is missing from the uploaded ZIP file attachment, I cannot really reproduce the issue.

Can you re-upload the complete model with all of the necessary data so that I can check it?

[Borys]

I re-uploaded the model

[Chris Maeder]

Note that I looked at your model. The problem is that you are attempting to control the turning on and off of the pump using the pump curve, and not using a control. It is because of this that you are getting instabilities in the model.

I recommend changing the pump curve so that it is more representative of head vs flow capacity, and then use a control rule to trigger the turning on and off of the pump.

Note that we provide an example model with StormNET that illustrates this. Look for the folder called "Lesson Pumps" in the StormNET folder. Let me know if you have further questions.