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CHEMKIN file not understood by OpenFOAM

Hello,
can somebody who is familiar with the CHEMKIN file format please help with the following problem?

I am trying to use the file [1] as thermo.dat input for the combustion solver. Although [2] says that the file is in CHEMKIN format, there seems to be at least one major incompatibility compared to the format description at [3]:

For example, lines 34-38 of [1] read:

Code:

oh         8/12/99 thermh   1o   1    0    0g   300.000  5000.000 1357.000    01

 2.62599754e+00 1.31992406e-03-3.59724670e-07 4.25630800e-11-1.82048016e-15    2

 4.12085374e+03 7.10667307e+00 3.43586219e+00 2.02235804e-04-1.13546412e-07    3

 2.42445149e-10-7.43651031e-14 3.74321252e+03 2.45014127e+00                   4

Columns 74...80 of line 34 are "0....01", although these colums must be "......1" according to [3]. What is the meaning of the additional digits? If I replace the unrecognized digits (here and elsewhere) with spaces, the reaction timing is wrong.

Anyone familiar with the CHEMKIN format, who can help?

Thank you
Helge

[1] https://www-pls.llnl.gov/data/docs/s...symp_therm.txt
[2] https://www-pls.llnl.gov/?url=scienc...uced_mechanism
[3] http://www2.galcit.caltech.edu/EDL/p...s/chemkin.html

Hi,

You can try to use libOpensmoke and the flamlet solvers developped by Tobias

Regards

I cannot really help you, but I can confirm the problem. ;)

Reading CHEMKIN mechanisms or thermo files with OpenFOAM is an adventures exercise. :mad:
I barely got any of the mechanisms from LLNL to work with OpenFOAM.

A workaround that I used for some smaller mechanisms was to convert the CHEMKIN files to OpenFOAM-format with

Code:

chemkinToFoam

and fix the occurring errors by hand. Apparently this isn't a really good solution. Also keep in mind that the CHEMKIN lexer is always the same.
On the plus side you get a "human readable" mechanism/thermo file that works for sure with OpenFOAM.

And maybe a last note concerning the thermo files: The common temperature of the two Cp/h/s polynomial (Tcommon) needs to be the same for all species. If this is not the case for your thermo data you need to refit the polynomials.

Cheers,
Armin

Oh and you can find a quite good description of the thermo data, i.e. NASA or JANAF polynomials, here:
http://www.me.berkeley.edu/gri_mech/data/nasa_plnm.html