Reacting Flows

Reacting Flows

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  2. Fluids - Reacting Flows
  3. I have loaded a Chemkin mechanism with reversible reactions into Fluent, and the mechanism reads in without an error (all the Chemkin output files are clear of errors). In the Fluent TUI, however I get a warning for each reversible surface reaction: Warning: Reversible surface reactions are not handled in Fluent. Made the reaction at line no. 25 irreversible When I check the finite rate reactions there are no reverse rates for any of the reversible surface reactions. I also cannot edit the reverse rate to enter any data. Are reverse surface reactions supported in Fluent? If yes, how can I enter the reverse rate parameters?

I have loaded a Chemkin mechanism with reversible reactions into Fluent, and the mechanism reads in without an error (all the Chemkin output files are clear of errors). In the Fluent TUI, however I get a warning for each reversible surface reaction: Warning: Reversible surface reactions are not handled in Fluent. Made the reaction at line no. 25 irreversible When I check the finite rate reactions there are no reverse rates for any of the reversible surface reactions. I also cannot edit the reverse rate to enter any data. Are reverse surface reactions supported in Fluent? If yes, how can I enter the reverse rate parameters?

Tagged: 19.2, Finite Rate Chemistry, fluent, fluid-dynamics, Species/Reactions
    • January 25, 2023 at 7:17 am
      FAQFAQ
      Participant

      This is a defect in the Fluent GUI. The warning message reflects a limitation of the Stiff Chemistry solver only. The Stiff Chemistry solver is unable to handle reversible surface reaction source terms. The Chemkin CFD solver will interpret the mechanism correctly, regardless of what is shown in the Finite Rate Reaction data for the material in Fluent. If you get this warning, the recommendation is to set the Chemistry Solver to Chemkin CFD, Apply this change (Look for the acknowledgement “Mixture material property method has been set to the default CKCFD solver settings.”) Then, read in your mechanism. (The warning about surface reactions being unsupported will still appear, but the rate data will actually be read correctly from the mechanism files at run time.) Set up and run the case as usual. while avoiding any visits to the finite rate Reaction panel.

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