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Failed to evaluate variable
Posted 20 févr. 2016, 21:19 UTC−5 Battery Design, Chemical Reaction Engineering, Results & Visualization Version 4.4 1 Reply
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Hi,
I am a new learner for COMSOL and apologize for asking some stupid questions.
I am using COMSOL to solve an electrochemical system under electroanalysis and I wish to plot a Nyquist plot. Somehow, I can't plot it out. What should i do when i see the error 'failed to evaluate variable' after compute ?
-Variable: elan.Zvsgrnd_els1
-Globe scope:
Failed to evaluate expression.
-Expression: conj(elan.Zvsgrnd_els1)
Failed to evaluate expression.
-Expression: real(conj(elan.Zvsgrnd_els1))
Failed to evaluate expression.
-Expression: real(conj(elan.Zvsgrnd_els1))
-Plot: nyq1 (Nyquist plot)
Regards.
I am a new learner for COMSOL and apologize for asking some stupid questions.
I am using COMSOL to solve an electrochemical system under electroanalysis and I wish to plot a Nyquist plot. Somehow, I can't plot it out. What should i do when i see the error 'failed to evaluate variable' after compute ?
-Variable: elan.Zvsgrnd_els1
-Globe scope:
Failed to evaluate expression.
-Expression: conj(elan.Zvsgrnd_els1)
Failed to evaluate expression.
-Expression: real(conj(elan.Zvsgrnd_els1))
Failed to evaluate expression.
-Expression: real(conj(elan.Zvsgrnd_els1))
-Plot: nyq1 (Nyquist plot)
Regards.
1 Reply Last Post 14 mars 2016, 05:51 UTC−4
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Posted:
9 years ago
Hi Mavis. I am also using COMSOL, and I currently am going through the learning curve.
So, when you have such an error it usually implies that COMSOL could not solve for the variables and expressions because you did something wrong in the meshing or you did not input the parameters well.
From experience, I have also learned to begin from 1D simulation and then progress to 2D, as in 1D you will get less of the errors, while still being able to understand COMSOL's functionalities.
elan.Zvsgrnd is usually the expression for impedance vs. ground (ohms.m^2). If COMSOL cannot calculate it at the different frequencies, then it won't be able to plot the graph
So, when you have such an error it usually implies that COMSOL could not solve for the variables and expressions because you did something wrong in the meshing or you did not input the parameters well.
From experience, I have also learned to begin from 1D simulation and then progress to 2D, as in 1D you will get less of the errors, while still being able to understand COMSOL's functionalities.
elan.Zvsgrnd is usually the expression for impedance vs. ground (ohms.m^2). If COMSOL cannot calculate it at the different frequencies, then it won't be able to plot the graph