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-   -   Add new species in time directory (http://www.cfd-online.com/Forums/openfoam/90836-add-new-species-time-directory.html)

goen July 21, 2011 14:15

Add new species in time directory
 
Hi everyone..
Pliss help me..

I want to do simulation with dieselEngineFoam. I want to add CH4 in time ( or in initial condition) directory. Probably, what should I do? What files should I change?

If someone can help me, it would be great.

Thanks
Goen

mturcios777 July 21, 2011 17:56

You will need to specify initial and boundary conditions for CH4 in the 0 directory (copy Ydefault to CH4 and modify it). Then you will need to ensure that your reaction mechanism included methane as a species (this will be in the chemkin directory; read the tutorials for reactingFoam to find out about reactions):

http://openfoamwiki.net/index.php/Tu..._firstTutorial

goen July 22, 2011 13:14

hi Marco.

Thanks for your answer. But I am still confused. I want to use two fuels. The first is c7h16 and second CH4. I want to put the CH4 in the combustion chamber as O2, N2 and others. I want to put in 0 directory. so it is not injected. What should I do? how to ensure that the correct reaction?.

Thanks
Goen

mturcios777 July 22, 2011 13:19

To ensure the correct reaction, you need to add the reactions and species to the chem.inp and therm.dat files. There is a lot of documentation on the proper format for these files, and you will need to determine what kind of reaction mechanism you are going to use.

goen July 22, 2011 14:30

Hi marco.

I have changed the file chem.inp and thermo.dat. how do you think about this:

ELEMENTS
H O C N AR
END
SPECIES
C7H16 O2 N2 CO H2O
O CO2 OH H H2
HO2 H2O2 N NO C
CH4
END
REACTIONS
C7H16 + 11O2 => 7CO2 + 8H2O 1.00E+8 0.0 15780.0! 1
FORD / C7H16 0.25 /
FORD / O2 1.5 /
CH4 + 2O2 => CO2 + 2H2O 1.50E+13 0.0 39718.0! 1
FORD / CH4 0.5 /
FORD / O2 1 /
(file in chem.inp)
is this correct?

do I also need to change the thermophysicalProperties file?.
then, what do you mean with:
"you will need to determine what kind of reaction mechanism you are going to use."

sorry, I am still confused
Thanks you for your patience

mturcios777 July 22, 2011 14:48

You've already decided which reaction mechanism you are using: single step. There are more complex ways that describe the reaction of methane with air that has intermediate reactions. You will need to make sure that the therm.dat has entries for the species that you have added (in this case, CH4).

This should be enough to get you started. Whether this is enough to get a correct solution is another matter that will take more effort to answer...

goen July 22, 2011 21:41

hi marco

I have added CH4 in the therm.dat. thanks for your answer. I will try to simulate it first.


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