Hi,
I have never had this problem before but when solving with a new demand added in an existing model in WaterCAD I get the error - "Disconnected Demand Nodes Detected" - the thing is it seems the pump stops working at 1 sec after the simulation runs. If it is the pump causing the error, i.e. cannot provide enough flow why don't I get that as the error rather?
Regards Hugh
Hello Hugh,
The disconnected demand nodes notification means that junctions are having demands which are not satisfied because they are disconnected from the source like tank or reservoir. Please go to the calculation summary and click on the time step for which you are getting disconnected demand nodes notification, in the status messages you will all the details about whats happening at that time-step.
Disconnected Demand Nodes user notification when computing model
If the pump stops working, then you should get notification about same as well, what is the version that you are using?
Regards,
Sushma Choure
Bentley Technical Suppport
Thanks Sushma, it seems unstable as the pump switches on and off in the same time step a few times. But I cannot work out why? As the tank it delivers to is not closed. If I change the demand back to zero, the model runs fine.
I am using 08.11.06.113 64 bit.
Have you checked the direction of Pump providing the flow? The direction of the mouth of the pump is the direction of flow.
To change it right click on the Pump and select Reverse. Run the model and check again.
Videet. The pump direction doesn't change. For many of the time steps the equation is solved but at other time steps I get the error.
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