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Modelica: Fluid from source, valve, to sink

asked 2019-06-17 16:15:39 -0500

first1 gravatar image

updated 2019-06-17 17:54:29 -0500

This next model I'm working on has a source with high pressure driving the movement of gas to the low pressure sink. In between the source and sink is a linear valve which I plan to be a control valve in the future. So source--> valve--> sink. The model will not solve because there exists one more variable than the total number of equations. The unknown variable is valve.port_a.m_flow.

It is not clear where or how I would define this variable. I thought that the pressure difference between source and sink would be enough to drive the movement of fluid. I did, however, see under the valve advanced settings that m_flow = port_a.m_flow. Not sure if that helps but I'm still confused.

valveTest

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answered 2019-06-17 18:03:59 -0500

You wrote "In between the source and sink is a linear valve which I plan to be a control valve in the future". If you used a valve, did you connect its control input signal? For getting started, see also https://simulationresearch.lbl.gov/mo..., the references in there, and https://simulationresearch.lbl.gov/mo...

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answered 2019-06-17 18:36:55 -0500

first1 gravatar image

I actually just realized I was using the wrong source signal and now it is working. Currently using a step signal. Thanks again!

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Asked: 2019-06-17 16:15:39 -0500

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Last updated: Jun 17 '19