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Methane/Air Combustion

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Hello all,

I am trying to recreate the OpenFOAM methane air combustion tutorial for reactingFoam and seem to be having some trouble starting the reaction. Any help would be great.


2 Replies Last Post Mar 17, 2017, 10:07 a.m. EDT

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Posted: 8 years ago Mar 17, 2017, 9:50 a.m. EDT
Hello,
If Ta = Ea/Rg = 14906 K, then Ea = Ta*Rg = 14906 K * 8.314 J/(mol K).
In your model you wrote Ea = 14906. [K] * (8314.5 [J/mol/K]), which is 1000x higher activation energy that in the OpenFoam tutorial.
-DW
Hello, If Ta = Ea/Rg = 14906 K, then Ea = Ta*Rg = 14906 K * 8.314 J/(mol K). In your model you wrote Ea = 14906. [K] * (8314.5 [J/mol/K]), which is 1000x higher activation energy that in the OpenFoam tutorial. -DW

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Posted: 8 years ago Mar 17, 2017, 10:07 a.m. EDT
Thank you for that, fun mistakes when your used to working in kmol. I replaced that as discussed and now run into an all to familiar error where I am having difficulties getting COMSOL to converge when all three physics models are used. I solve for the flow and transport of concentrated species together and then use those as the basis for a new study like the Syngas Combustion tutorial. It always ends with a Temperature T division by zero error. I have adjusted the pseudo time-stepping CFL number in the segregated solver to no avail.

-Robert
Thank you for that, fun mistakes when your used to working in kmol. I replaced that as discussed and now run into an all to familiar error where I am having difficulties getting COMSOL to converge when all three physics models are used. I solve for the flow and transport of concentrated species together and then use those as the basis for a new study like the Syngas Combustion tutorial. It always ends with a Temperature T division by zero error. I have adjusted the pseudo time-stepping CFL number in the segregated solver to no avail. -Robert

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