[prapanj]

Hi Friends,

I found this wonderful code fireFoam chiefly worked on by FMGlobal, they have a goodle codes page.

After downloading and compiling the sources, I tried to run their tutorials. All three tutorials crash with the error

Reading field U



--> FOAM FATAL ERROR: 
Not implemented

    From function basicThermo::hs()
    in file basicThermo/basicThermo.C at line 304.

FOAM aborting

#0  Foam::error::printStack(Foam::Ostream&) in "/home/rwdi-india/OpenFOAM/OpenFOAM-1.6.x/lib/linuxGccDPOpt/libOpenFOAM.so"
#1  Foam::error::abort() in "/home/rwdi-india/OpenFOAM/OpenFOAM-1.6.x/lib/linuxGccDPOpt/libOpenFOAM.so"
#2  Foam::basicThermo::hs() in "/home/rwdi-india/OpenFOAM/OpenFOAM-1.6.x/lib/linuxGccDPOpt/libbasicThermophysicalModels.so"
#3  main in "/home/rwdi-india/OpenFOAM/rwdi-india-1.6.x/applications/bin/linuxGccDPOpt/fireFoam"
#4  __libc_start_main in "/lib/tls/i686/cmov/libc.so.6"
#5  _start in "/home/rwdi-india/OpenFOAM/rwdi-india-1.6.x/applications/bin/linuxGccDPOpt/fireFoam"
Aborted

Can someone please help me identify what is wrong?

Thank you
Prapanj.

[braennstroem]

In addition, there is fireFoam in the latest git... unfortunately, I do not know the differences yet.

Fabian

[prapanj]

I have been looking around both versions of fireFoam and I found the one provided in the google codes page to be superior ( at least the latter has solid phase pyrolysis boundary conditions ). Another difference I noticed was with a field called fu in the git version which is not present in the other version.

I believe the git version can only solve for gaseous fuel injected into a combustion chamber and not accound for burning of solids.

Does anyone have an idea how to visualize soot and the other combustion products like C02 etc. ?

I hope someone got either of them working and has done some simulation.

[jason_wy]

Prapanj,

FireFOAM released in googelCode was tested in OF-1.6. There is some changes in 1.6.x in basicThermo that causes the error you see. I have updated googleCode so that the solver is compatible with 1.6.x. You just need to check it out use:

svn checkout http://firefoam-dev.googlecode.com/svn/trunk/ firefoam-dev-read-only

Let me know if it solves your problem.

Yi

[jason_wy]

Both versions of fireFOAM are the products of collaborations between FMGlobal and OpenCFD, and they are currently under tests and further developments.

The one released in googleCode is using total enthalpy. The one released recently in 1.6.x is using sensible enthalpy equation. The chice of which equations to use has implications in numerics as well as the combusion models. However I believe both codes are useful, and the choice can be dependent on the needs of your simulation.

Yi

[prapanj]

Thank you Yi,

That works. My need is to be able to simulate pyrolysis of solid phase. After going through the presentations on the google code page of fireFoam, I found that fireFoam has this capability. But then I did a grep 'pyrolysis' and found that this BC was not implemented in the OF 1.6.x version of fireFoam. Hence concluded that the one on the google code page is superior than one available with OF.

Please correct my understanding if I am wrong and mention any other important differences here. Thank you.

Prapanj

[prapanj]

Now that I have started running fireFoam, I have the following questions. I really read most of the presentations on the codes page and still have these questions. Bear with me :P

1. How do I visualize soot(concentration)? And for that matter any other product of the combustion - eg) CO2.
2. I understand ft as mixture fraction(by mass) of the fuel. What is fu? What is ftVar ?
3. What is Pr and Qr ? Does ox mean oxidant fraction?

I know some of these questions are basic and the answers may be straightforward from the code. But answers here could make things much clearer for beginners for firefoam like me

Thanks
Prapanj

[jason_wy]

Prapanj,

We are still working on refinement and validation of pyrolysis model. The presentation is our working progress. We will release the pyrolysis capability when we are ready. Most probably some time next year.

To answer your other questions:
1. Again, no soot capability now in the released version. But one can easily add some simple soot model in.
2. ft is mixture fraction. fu is the fuel mass fraction. ftVar is the variance of mixture fraction.
3. Pr - mass fraction of product. Ox - mass fraction of oxdiant. Qr is the net radiant heat flux on boundaries.

Yi

[alberto]

Originally Posted by jason_wy

2. ft is mixture fraction. fu is the fuel mass fraction. ftVar is the variance of mixture fraction.
3. Pr - mass fraction of product. Ox - mass fraction of oxdiant. Qr is the net radiant heat flux on boundaries.

Hello,

some hint to make the nomenclature self-explanatory :

ft -> mixFrac, Ymix (X if condensed, Y if vapour) or csi
ftVar -> sigmaYmix
fu -> fuelFrac, Yfuel
Pr -> Yprod
Ox -> YOx

I prefer the "Y" notation, but as long as it is not cryptic, it's OK.

I know it is a bit heavier to code, but in my opinion it really improves the readability.

Anyway, very interesting job

Best,
Alberto

[prapanj]

Hi,

Thank you Yi and Alberto. Now, fu is not present in the googlecodes version of fireFoam. And I feel the presense of ft and fu fields redundant. If not, please correct me. And Ox should then be "1.0 - ft " am I right?

Pr is not present in the OF-1.6.x git version. And following the presentations I tried using pyrolysis BCs and I don't find them implemented in both versions. Could someone give a short account of the differences between both versions and talk about whether are not pyrolysis of solids is present in either of the versions ?

Thank you
Prapanj.

[piccinini]

Would anybody know if fireFoam is proper to simulate Sandia (piloted) flame D?

I've seen that it's a LES with pdf mixture model and low mach number formulation. So far, the only limitation I noticed is the infinitely fast chemistry.

thanks.

[braennstroem]

Hi,

does anyone know what kind of 'smallpoolfire' is distributed with the official tutorial? I have trouble to understand the speciesTable and the thermophysicalProperties...

Thanks!
Fabian

[mabinty]

dear all!

I had a look on the code of fireFoam-1.6-1.0 and saw that for the pressure equation the formulation p = pd +roh*g*h (+ pRef) is used, what was changed from 1.5 to 1.6 for solvers based on buoyantPisoFoam where only p is used. what is the reason for keeping the formulation using pd?

thanks for your comments!

aram

[yashar.afarin]

Hi everybody ;

does anybody use fireFoam for modeling combustion of annular(sandia flame) or planar jet ?

[jason_wy]

FireFoam assumes infinitely fast chemistry. It will be hard to do sandia flame without some decription of chemistry. Really depends on what you want to achieve.

[yashar.afarin]

Thank You Yi.
my project is about modeling the equilibrium flame in planar turbulent jet by LES and I think fireFOAM is the best choice. I think fast chemistry is suitable for my case. do you have any toturial about fireFOAM with more details?

[windwin]

hi yi

i have some questions about firefoam, in fact there is a solver named firefoam in the tutorial of openfoam, why we download a another one ? whats the differences between the 2?

thank you

best

[anfho]

Hi All,
I had a question regarding the units used for the sensible enthalpy for fireFoam in the OF 1.7.1 release.

Am I right in assuming that the units for the sensible enthalpy, hs are in J/kg?

Thanks,
Andreas

[sebastien_F1]

Hi anfo,

You're right. The unit for sensible enthalpy are in J/kg or m^2/s^2.

thanks,

Hi windwin,

In openfoam, it's an old and basic version of firefoam. If you open this directory :
OpenFoam-1.7.x/applications/solvers/combustion/fireFoam/

you will see that it's almost empty and there is just a combustion model. You will noticed that it doesn't contain pyrolisis, surfacefilm models, etc...

thanks

sebastien

[babakflame]

Dear Buddies
Hi
would somebody plz hint me what is the combustion model of firefoam, cause a firned told me that is has flamelet model. Is he right?