[tsencic]

The tutorial concerning diesel is done with heptane C7H16. I would like to use different hidrocarbons, for example C12H26. I know I have to change the species, the reactions and the coeffs in chemkin/chem.inp and the nasa polinomials in chemkin/term.dat. I supose also in constant/thermophysicalproperties i should ad some coeffs but I do not know how.

What do I have to change to use a different fuel then those mentioned in chemkin/therm.dat?

[tsencic]

I found the IDEA fuel in the src/thermophysicalModels/liquids directory, but I do not know how to use it.
What do I have to do in order to use the IDEA fuel?

Hi. Tomislav

You can use the fuel by changing the liquidFuelComponents in constant/thermophysicalProperties.

[tsencic]

Thanks.
I tried but I receive again some errors.
Do I have to change the reactions and the species in chem.inp? Do I have to put the reactions for both the components of IDEA (C10H7-CH3 and N-C10H22(DECANE)? Where can I find the reaction coefficients?
Do I have to change something in chemkin/thermo.dat?

[tsencic]

I tried to use C14H30. I changed chem.inp with the reaction
2C14H30 + 43O2 => 28CO2 + 30H2O
but I get

--> FOAM FATAL ERROR : Elemental imbalance in H in reaction
irreversibleArrheniusReaction
2C14H30^0.25 + 43O2^1.5 = 28CO2 + 30H2O
(2.81171e+06 0 7940.36)
on line 10

What is the reason?

[lucchini]

Hi Tomislav,

Try with the following

C14H30 + 21.5 O2 => 14CO2 + 15H2O

and see what happens.

bye

[guido_adriaensen]

Hello,

Shouldn't you be using:

C14H30 + 21 O2 => 14 CO2 + 15 H2O

The O was in imbalance.

Guido

[guido_adriaensen]

Sorry,

Never mind my post :-) Thought there was something else written there.
Tommaso's post was correct, sorry again.

[lucchini]

Tomislav,

it seems to be something related to the coefficients:

FORD / C14H30 0.25 /
FORD / O2 1.5 /

Try to investigate what they mean.

[tsencic]

Yes, I just left them from the tutorial for C7H16. I 'll try to investigate.
Anyway, thanks

[Abhishekd18]

Hi everyone,

I am trying to run sprayFoam. I am using C12H26 and have added the specie in therm.dat and reaction in chem.inp.

ELEMENTS
H O C N AR
END
SPECIE
C12H26 O2 N2 CO2 H2O
END
REACTIONS
2C12H26 + 37O2 => 24CO2 + 26H2O 3.00E+5 0.0 15780.0! 1
FORD / C12H26 0.75 /
FORD / O2 1.5 /
END

I am getting following error.

--> FOAM FATAL ERROR: Elemental imbalance in H in reaction irreversibleArrheniusReaction 2C12H26^0.75 + 37O2^1.5 = 24CO2 + 26H2O on line 10 From function chemkinReader::addReaction in file chemistryReaders/chemkinReader/chemkinReader.C at line 782. FOAM exiting

Where is the imbalance?

[RobertoTorelli]

Hi everyone!
I have a question for Abhishekd18 (and also for everyone who could help me). Did you solve the problem of the reaction imbalance? I have the same problem and I also tried to divide by 2 all the reaction coefficients in order to have a unitary coefficient for the dodecane, but still nothing... Furthermore I have updated my therm.dat with the correct janaf coefficients, so I think the problem is related only to the chem.imp file.
I hope you could help me and thanks in advance! :-)

Roberto

[juanma]

Originally Posted by Abhishekd18

Hi everyone,

I am trying to run sprayFoam. I am using C12H26 and have added the specie in therm.dat and reaction in chem.inp.

ELEMENTS
H O C N AR
END
SPECIE
C12H26 O2 N2 CO2 H2O
END
REACTIONS
2C12H26 + 37O2 => 24CO2 + 26H2O 3.00E+5 0.0 15780.0! 1
FORD / C12H26 0.75 /
FORD / O2 1.5 /
END

I am getting following error.

--> FOAM FATAL ERROR: Elemental imbalance in H in reaction irreversibleArrheniusReaction 2C12H26^0.75 + 37O2^1.5 = 24CO2 + 26H2O on line 10 From function chemkinReader::addReaction in file chemistryReaders/chemkinReader/chemkinReader.C at line 782. FOAM exiting

Where is the imbalance?

Hi Abhishekd,

Where did you get the JANAF coefficients for C12H26 from? Could you please share them?
Thanks!
Juanma