[Tobi]

Hi all,


first thanks to zubs (Bernhard). He told me that there is a error while compiling the simple solver. I did a definition two times. I updated the solver and now everything is working.

second.

I had a meeting with my advicer but there is no way to get the thesis completely or parts of it. The only way it should be possible is to make a paper but therefor I have no time

But if you have questions, you can ask me or email me!

Keep SMOKING

[babakflame]

Dear Tobi
Hi
I have a question about the adiabatic mode. Do we need to use the adiabatic mode for modeling a combustion chamber and if yes, Why?

[Tobi]

If you use the adiabatic mode you have no head lose. You can test your chamber with the adiabatic mode and then using the non-adiabatic mode (radiation model turned off) to compare the differences.

[nichkoohi]

DEAR TOBI
I SAW YOUR opensmoke code , i think it is same as the code that developed on rostok university by hanns kroger. there is an application for les -flamelet that called FGM. do you see it?if ya, what is your idea about it?

[Tobi]

Originally Posted by nichkoohi

DEAR TOBI
I SAW YOUR opensmoke code , i think it is same as the code that developed on rostok university by hanns kroger. there is an application for les -flamelet that called FGM. do you see it?if ya, what is your idea about it?

Hi,
do you have a link to the code?
Then I ll have a look at it.

Tobi

[wyldckat]

Hi Tobi and Ali,

I was curious and did a little searching on this... I think it's this one: http://openfoamwiki.net/index.php/Si...e_contribution

Best regards,
Bruno

[nichkoohi]

dear tobi
thanks
because the server is changed, the new link of the source code of LTTRostockExtensions is here
http://www.kroegeronline.net/exchang...Extensions.tgz.

[Tobi]

Hi,

I had a look at the downloadlink and untared the folder.
Unfortunatelly there are so many folders that its not possible to tell you if its the same like Alberto `s Libs.

I read something about beta-pdf but the whole stuff includes more than the flamelet-LES model (I think).

Sorry.

[nichkoohi]

hi tobi
thank u for your attention. sir do u see firefoam solver on O.F 2.0.0 i think it is a solver for diffusion flame with unsteady flamelet aspect that use both LES and RANS for turbulence modeling. am i right?

[babakflame]

Dear All guys
Hi
I think firefoam was first built by infinitelyfast chemistry , However it was evolved by adding unsteadyflamelet to it. Although the aim was calculating soot-radiation interaction, It is capable of calculating transient flames using LES method.

[Tobi]

Hi Ali,

you asked me if the firefoam is based on flamelet.
I told you that it is not based on it but I am not sure.

In my study I had no combustion and I am not a combustion expert.
I am only good in the flamelet-solver of alberto cuoci.

So forget the things I told you yesterday.
Tobi

[nichkoohi]

dear babak
sir as regarded to notation of tobi, i think the firefoam cannot calculate the all species mass fraction, as u know the flamelet model include a table that consider all reactive species but i think fireFoam consider only product and reactant mass fraction. however, assume firefoam can based on flame let, do u describe how it calculate the table?
i wait u.

[babakflame]

Dear Tobi
Hi
I have started converting your flamelet code into LES. I have studied ur code piece by piece. I think that first of all I should change the main solver from SimpleC to Pimple with some modifications obligatory for flamelet calculations. Some fine modifications also needed for create fields file. But the primary question for me is in the csi.H file. The equations of mixture fraction and it's variance. My own belief is that this file (although it seems at first sight wrong) does not need any modifications cause the turbulent coefficients in these equations do not depend on the turbulence method. I mean for instance in the line:

Cd*rho*turbulnce->epsilon () / (turbulence->k() + k_small)*csiv2

the mentioned coefficients should be written the same for both turbulence methods. I mean that they do not depend on RANS so in LES they stay immutable.

Am I right buddy? Would u plz speculate about my suggestions.
Regards
Bobi

[Tobi]

Originally Posted by babakflame

Dear Tobi
Hi
I have started converting your flamelet code into LES. I have studied ur code piece by piece. I think that first of all I should change the main solver from SimpleC to Pimple with some modifications obligatory for flamelet calculations. Some fine modifications also needed for create fields file. But the primary question for me is in the csi.H file. The equations of mixture fraction and it's variance. My own belief is that this file (although it seems at first sight wrong) does not need any modifications cause the turbulent coefficients in these equations do not depend on the turbulence method. I mean for instance in the line:

Cd*rho*turbulnce->epsilon () / (turbulence->k() + k_small)*csiv2

the mentioned coefficients should be written the same for both method.

Am I right buddy? Would u plz speculate about my suggestions.
Regards
Bobi

Hi Bobi,

I can not give you an anwer about that question.

[Tobi]

Hey all,

it seems that Alberto and his team are working on a new homepage:
http://creckmodeling.chem.polimi.it

So I think we all have the new libOpenSmoke in a few days/weeks


Tobi

[babakflame]

Hi Tobi
Oh, Thanks god. I hope we will have the new version with LES method.

[babakflame]

Dear Tobi
Hi
In the RAS-flamelet code we have a parameter in the results that is so called:
Planck mean absorption coefficient (as)
I think it relates to radiation heat transfer, However I do not know further about it. Would u plz give me a hint or maybe allude to references.

Regards
Bobi

[Tobi]

Hi Bobi,

you are right.
That coefficient is for the radiation model and is calculated in the flamelet pre-processing.

For references:

http://www.sandia.gov/TNF/radiation.html

Tobi

[babakflame]

Dear Tobi

I have downloaded the C1C16 High temperature mechanism from Creckmodeling site. When I tried to pre-process the Chemkin format, I got this error message:

** Reading thermodynamic database...
terminate called after throwing an instance of 'std:ut_of_range'
what(): basic_string::substr
./Run.sh: line 1: 6817 Aborted ../../../exe/OpenSMOKE_CHEMKINInterpreter.sh --kinetics "PolimiC1C6HT_1212.kin" --thermo "termo_1212.tdc" --transport "tran_1212.tra" --output "PolimiC1C6HT"

Would u plz help we that what is the problem?

I think it's because of the .kin file name ( I used one of the file name's existed in the opensmoke code and it solved) , however Iam still confused.

I have another important question tobi.
What if we want to have a mixture of two fuels instead of one fuel, For instance if we have both propane & n-butane, which of them should be mentioned as fuel in Data.inp file?

[babakflame]

Dear Tobi
Hi
Would u plz hint me that in the Sandia CH4H2N2 2D case, How does the values for k & epsilon be calculated for the inlet air and fuel? (Forexample the following lines

inletfuel
{
type turbulentIntensityKineticEnergyInlet;
intensity 0.2;
U U;
phi phi;
value uniform 239.65;
}

For instance, If I change the fuel from CH4 to C3H8 without any changes in velocity magnitude, Does these values change?
Regards
Bobi