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Tmax in reactingFoam depends on CFL-number (?)

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Old   June 20, 2011, 13:55
Default Tmax in reactingFoam depends on CFL-number (?)
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Andras Horvath
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Dear Foamers,
I am using OpenFoam-1.7.1 (git: 03e7e056c215). There is a tight dependence between "T gas max" and the CFL number in the reactingFoam tutorial case. Lower Courant-numbers lead to lower maximum temperatures and vice versa.

In "applications/solvers/combustion/reactingFoam/chemistry.H" the line

// Chalmers PaSR model
kappa = (runTime.deltaT() + tc)/(runTime.deltaT() + tc + tk);

with an _absolute_ runTime.deltaT() clearly is an error, isn't it?

Also to test mesh dependence i tried this:

I refined the original mesh from the tutorial from 4000 -> 400000 cells (x10 in both directions) and ran the tutorial again. It crashes both in single and parallel at around 0.0007s. I also tried removing runTime.deltaT() from the kappa-equation in the source code, recompiled it, and ran it to the same effect. At some point epsilon becomes negative and the solver crashes.

Any ideas?


Cheers,
Andras

Last edited by andras; July 5, 2011 at 08:15.
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cfl-number, reactingfoam, temperature

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