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Tank in Series with Known Demands Issue


I'm trying to setup a scenario where a supply (Reservoir 1) fills Tank 17 at a specified flowrate. A FCV is used on the line between the reservoir and Tank 17 to set the Flow, 168-GPM. Tank 17 fills from the bottom and has a separate pipe for the outflow. The Tank 17 outflow pipe tees splitting flow into two separate directions. The first is to Tank 12 (16,000-ft away). Tank 12 has a separate inflow and outflow pipe. The Tank 12 outflow pipe has a known demand (86-GPM). The second branch for water exiting Tank 17 tees to a junction with a known demand, called Tank 22 Pumped Demand, 71-GPM.

The summary graphs for Tank 17 and Tank 12 show that they appear to fill in a logical time period. Tank 17 is the first tank online and fills in 15-hrs. The graph shows it oscillates between filling and emptying until Tank 12 is full, 29-hrs. Everything beyond that generates user notifications which create concern that flow is not actually making it out of Tank 17. Numerous system disconnected errors and pressures below physically possible pressure in system as well as notification that FCV can't deliver flow. The notifications show Tank 17 and 12 both fill but the pipe segments between show no flow in the properties dialog boxes.

A scenario was created to have two demands setup on the system as mentioned above. The results are not realistic. The hydraulic grade for the system appears to be completely off and it also shows Tank 12 actually flowing back toward the other junction with a known demand. 

Using the network navigator to trace downstream, starting from reservoir 1 the highlighted route stops at Tank 17. Are we missing something to have flow coming out of each Tank?

Should a scenario like this run as a steady state or EPS.

Is there a better way to model Tank 17 filling at a specified rate. Other forums discussed the PSV and the FCV which has been modeled. 

Any sage advice would be greatly appreciated. We also tried creating a smaller model but run into similar issues. Below is an image of the scenario, but slightly modified in the actual model.

Here is a link to Onedrive with the actual waterCAD file if anyone has time to review.

Thank you,


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