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If I build a model in Dymola, but in translation, there is a warning about incompatible units of equations, but just according to the warning message, I can't find which components that the wrong equations belong to. So how could I find it in Dymola?

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Jack
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  • You can see in the equations the component names. In general der(heatExchangerFixedTemperature.EB) means that the component heatExchangerFixedTemperature contains the component EB and equation der(EB). Sometimes that is not the case if you refer to components more deeper in the hierarchy in the equations. – Adrian Pop Nov 23 '20 at 18:42
  • Actually, in my model, there is no component called "heatExchangerFixedTemerature", making it hard to find the error source. – Jack Nov 24 '20 at 07:00
  • Somehow, I think Dymola could give us the information about which components the wrong equations belong to, but choose not to do. I am not sure why. – Jack Nov 24 '20 at 10:54

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I agree that Dymola should include more information about equations in unit-checking. However, we can see that:

  • It doesn't seem to be in a function, as it is an equation for a derivative.
  • It doesn't seem to be in heatExchangerFixedTemperature as all variables do not start with that prefix (unless T_amb is a package constant). It would thus seem that the equation is directly in the current model, or in one of its base-classes.
Hans Olsson
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  • So, the best solution right now is checking the code line by line. Debugging is always a painful part. I suggest that Dymola could make a survey about needs during debugging and improve it. – Jack Nov 24 '20 at 12:40
  • In the meantime, I think it is better if there is a tutorial about how to find the error source, especially for beginners. – Jack Nov 24 '20 at 12:42
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    Most error messages give more context, but the unit-checking is a bit lacking. – Hans Olsson Nov 24 '20 at 12:56
  • Nonlinearity is also a problem, Dymola should tell users where to find the nonlinear equations instead of just showing how many ones in the model. – Jack Nov 24 '20 at 13:01