Error running GRI-Mech3.0 example: ForbiddenStructureException for species CH

[robertajaques-bauer]

Hi RMG team,

I tried to run the example located at:

examples/rmg/gri_mech_rxn_lib

However, the simulation crashes with the following error message:

Error running GRI-Mech3.0 example: ForbiddenStructureException for species CH

This happens during the execution of add_reaction_library_to_edge, suggesting that the CH species is not allowed by default constraints, even though it is present in the GRI-Mech3.0 reaction library.

Here are some additional warning messages I got before the crash:

LinAlgWarning: Ill-conditioned matrix (rcond=...): result may not be accurate.

Environment:

• Using the official rmg_env (Python 3.7)
• Running via the Docker image
• GRI-Mech3.0 is included in the thermoLibraries field

Is this a known issue? Should I manually adjust the species constraints to allow CH, or is there a recommended workaround?

Thanks in advance!

Best regards,
Roberta

[jonwzheng]

Hi Roberta,
Thank you for posting the issue. Yes, I was able to recreate this. I'm not sure why this file fell out-of-date; probably the input file was probably created before the SpeciesConstraints were added.

To fix this, add this to input.py:

generatedSpeciesConstraints(
    maximumCarbeneRadicals=2,
)

[jonwzheng]

BTW, I have started a new PR (#2824) which will update these examples for everyone. Thank you again for finding this error!