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EPANET alternating nodes with base demand 1

kikonas68

Mechanical
Feb 13, 2024
19
Hello.
I have drawn the network with all its nodes(with their respective base demands) and its reservoir.
Is there a way to run the simulation several times so that each time only specific nodes are "open"(having the base demand already assigned) and for the rest of the nodes base demand is considered zero(ignoring the base demand already assigned).
Imagine e.g. an irrigation network where during the day valves open and close with alternance.
Thanks in advance.
 
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I don't think this can be automated in EPANET. One work around that comes to mind would be to set each node it's own demand pattern, such that only one node activates at a time. Then let the simulation run through all your nodes.

Consider that your reservoir level must remain within the range you want to test throughout the entirety of the simuation, which could be an issue depending on your situation.
 
Yes there is. Set up a time period simulation where time doesn't matter. That is, set up demand patterns that alternate the flows and/or set up valves that open and close at different times via rules. I do this a lot for moving fire flows around a network and for developing systems curves for pumping stations. When I can find it, I will post an example.
 
OK, here is my "Simple Pumping Station Model". I had to take my most recent version and delete company logos so I could share it here. I built this model long before I joined my current company, so I'm free to share it. It's just that the last time I shared it was internally, and I had added the company logo to various files.

Here is what is in the .zip file Simple Pumping Station (EPANET + EXCEL) - Generic.zip:
  • FEL_Simple Pumping Station Model_System Curves.inp — This text file is the EPANET input file for the simple pumping station. Load it into EPANET via File|Open and in the "Files of type:" box, select "Input file (*.INP)". This is also the file to look at to see how I built the model. The introductory text will help you quite a bit.
  • FEL_Simple Pumping Station Model_System Curves.net — After I ran the model from the .inp file, I saved the .net file, which is the complete model in EPANET's proprietary format.
  • FEL_Simple Pumping Station Model_System Curves.rpt — After I ran the model, I created this report via Report|Full.
  • FEL_Simple Pumping Station Model.xltx — After I ran the model, I pulled pump suction and discharge HGLs from the report and entered them into this spreadsheet template for generating the systems curves. I then added two made-up pumps for graphing purposes. I made this a template instead of a regular spreadsheet so that I don't accidentally overwrite my master document.
  • FEL_NPSH.mctx (Mathcad Prime 9.0) and FEL_NPSH.pdf — These files calculate Net Positive Suction Head for pumps. I included the Mathcad template file in case you have MCP 9.0 or later. Otherwise, you can use the .pdf file.
  • FEL_Submergence for Submersible Pumps.mctx (Mathcad Prime 9.0) and FEL_Submergence for Submersible Pumps.pdf — These files calculate submergence requirements for submersible pumps. I included these files because most recently I have been designing small wastewater and stormwater lift stations with submersible pumps.
I you have any questions, please holler.
 

Attachments

  • Simple Pumping Station (EPANET + EXCEL) - Generic.zip
    1.2 MB · Views: 2
Thanks a lot for sharing and your time spent
OK, here is my "Simple Pumping Station Model". I had to take my most recent version and delete company logos so I could share it here. I built this model long before I joined my current company, so I'm free to share it. It's just that the last time I shared it was internally, and I had added the company logo to various files.

Here is what is in the .zip file Simple Pumping Station (EPANET + EXCEL) - Generic.zip:
  • FEL_Simple Pumping Station Model_System Curves.inp — This text file is the EPANET input file for the simple pumping station. Load it into EPANET via File|Open and in the "Files of type:" box, select "Input file (*.INP)". This is also the file to look at to see how I built the model. The introductory text will help you quite a bit.
  • FEL_Simple Pumping Station Model_System Curves.net — After I ran the model from the .inp file, I saved the .net file, which is the complete model in EPANET's proprietary format.
  • FEL_Simple Pumping Station Model_System Curves.rpt — After I ran the model, I created this report via Report|Full.
  • FEL_Simple Pumping Station Model.xltx — After I ran the model, I pulled pump suction and discharge HGLs from the report and entered them into this spreadsheet template for generating the systems curves. I then added two made-up pumps for graphing purposes. I made this a template instead of a regular spreadsheet so that I don't accidentally overwrite my master document.
  • FEL_NPSH.mctx (Mathcad Prime 9.0) and FEL_NPSH.pdf — These files calculate Net Positive Suction Head for pumps. I included the Mathcad template file in case you have MCP 9.0 or later. Otherwise, you can use the .pdf file.
  • FEL_Submergence for Submersible Pumps.mctx (Mathcad Prime 9.0) and FEL_Submergence for Submersible Pumps.pdf — These files calculate submergence requirements for submersible pumps. I included these files because most recently I have been designing small wastewater and stormwater lift stations with submersible pumps.
I you have any questions, please holler.
Much appreciated you sharing all this and the time spent.
 
I don't think this can be automated in EPANET. One work around that comes to mind would be to set each node it's own demand pattern, such that only one node activates at a time. Then let the simulation run through all your nodes.

Consider that your reservoir level must remain within the range you want to test throughout the entirety of the simuation, which could be an issue depending on your situation.
Thanks. That's the basic idea I was looking for.
 

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