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Negative temperatures with radiation exchange model

What is the problem?

  • Solver calculates negative values when solving Stefan-Boltzmann equation in AixLib.Utilities.HeatTransfer.HeatToStar

Why do we want to solve it?

  • Although the solution is correct from a mathematical point of view, negative temperatures must be avoided.

How do we want to solve it?

  • ...

Further description

I have a reproducible total model, in which the error occurs, when using lsodar. With dassl the simulation runs successfully.

@Mathadon and @rubenbaetens: I found your old issue, after I inspected the model IDEAS.Buildings.Components.BaseClasses.RadiativeHeatTransfer.HeatRadiation. By default linearise = true you use the linearized function instead of the biquadratic one. But have you ever encountered a problem like the screenshot shows when you used the biquadratic function? And if yes is there any solution for this problem?

Thanks a lot in advance for any help!

Screenshot: image