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Error simulating a chiller using the buildings library in Open Modelica.

asked 2017-09-21 00:55:43 -0500

Siv's avatar

updated 2017-09-21 10:31:58 -0500

When I try to simulate the model, the following error presents itself.

Variable Chiller: Cyclically dependent constants or parameters found in scope 
Buildings.Fluid.Chillers.Carnot_TEva$Chiller: {COP_nominal,etaCarnot_nominal}.

Could someone please tell me how I can overcome this issue?

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Without more details it's hard to tell you where the cyclical parameters are...

Julien Marrec's avatar Julien Marrec  ( 2017-09-21 10:20:29 -0500 )edit

Hi, sorry for the delayed response. However, Could you please tell me what additional details might be necessary ?Anyway, I was able to overcome this issue using -d = ignoreCycles in Tools>Options>Simulation.

But I am unable to understand what is running in the background. Previously the simulation never ran when this error occurred. But now it runs and still displays the error. Are the results reliable ?

The example I ma trying to run is Buildings.Fluid.Chillers.Examples.Carnot_TEva

Thank you for your response in advance.

Siv's avatar Siv  ( 2018-08-06 07:12:01 -0500 )edit

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answered 2017-09-21 17:39:16 -0500

This looks like a bug in OpenModelica as the Carnot chiller and Carnot heat pumps all work in JModelica and in Dymola.

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Could you please explain the nature of this bug or describe this error a bit more in detail?

Siv's avatar Siv  ( 2017-10-08 14:11:44 -0500 )edit

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Asked: 2017-09-21 00:55:43 -0500

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Last updated: Sep 21 '17