[danielb]

Hello,
is there any kind soul, who can summarize the differences between reactingFoam, XiFoam, dieselFoam and fireFoam?

Which of them is appropriate to calculate the combustion of non-premixed biofuel that evaporates from a curved surface, which is wetted with fuel?

For the beginning, any simple combustion reaction will do. The exact kinetics are currently developed, and we will include them later.

(We have found that dieselFoam is no longer available in openfoam 2.2.1. Is is correct that sprayFoam offers the same functionality? Are there any tutorials that document the sprayFoam usage in a similar fashion like the aachenBomb tutorial for dieselFoam?
Finally, we tried to compile openfoam 1.7.x from the git repositories in order to be able to run dieselFoam. Unfortunately, openfoam 1.7.x cannot be compiled with recent gcc versions (gcc-4.8.1 in ubuntu 13.10), as already discussed in these forums. Are openfoam 1.7 binaries available for ubuntu 13.10? Or do you know of a reliable documentation about how to compile openfoam 1.7 in ubuntu 13.10?)

Thank you
Daniel

[danielb]

Nobody?

I am looking for a transient solver that implements a liquid and a gas phase including evaporation at the liquid-gas interface, ignition and chemical reactions.

Is any of the combustion solvers appropriate for thi tasks?

Thank you
Daniel

[mturcios777]

It seems that either sprayFoam or fireFoam would do the trick with some fancy boundary conditions, as droplet evaporation from a wetted surface isn't implemented I believe. You could cheat and have a droplet source if you knew the rate of evaporation..

[danielb]

Thank you,
it seems like fireFoam and sprayFoam include most of the needed functions. I have a question about the evaporationModels, though.
It seems that they use analytic expressions for droplets (similar to the d^2 decay) rather than solving the gas-liquid equilibrium across the interface numerically.
Is this right? Or can you show me the part of the code that implements the boundary condition for the evaporation?

Thank you
Daniel

[mturcios777]

The phase change models account for the liquid/gas properties, but I'm not sure how the interface affects evaporation (I believe there is an assumption that all droplets are spherical). The code for phase changes can be found in $FOAM_SRC/lagrangian/intermediate/submodels/Reacting/PhaseChangeModel.

There are also the lagrangian solvers, and reactingParcelFilmFoam might be the closest to what you are looking for.

[mehtab]

I am working on pool fire problem in fireFoam. I am looking for a transient solver with liquid and gas phase coupling including evaporation at liquid gas interface.

FireFoam is quite good for gas phase combustion for diffusion flames. Is it possible to add another solver (to account for heat/mass transfer in liquid phase) in fireFoam and liquid evaporation at the interface?

Thanks
Maqsood

[Zhiheng Wang]

Hi there,
I know its late but i am writing on basis of my limited knowledge
Yes it is possible but what you are exactly doing in pool fire i have added evaporation code on basis of thermal spalding number model, If you are going to solve Gas Phase equation along with liquid phase equation. Check with reactingTwoPhaseEulerFoam on openFoam 3.0
regards

[lx882211]

Originally Posted by mturcios777

It seems that either sprayFoam or fireFoam would do the trick with some fancy boundary conditions, as droplet evaporation from a wetted surface isn't implemented I believe. You could cheat and have a droplet source if you knew the rate of evaporation..

I meet a problem in Openfoam 2.3.0, reactingFoam, i need the data of CH4 reaction rate, but i failed to autowrite it like U or Yi.

First i added this code in the CreatField.H,

volScalarField Rrate
(
IOobject
(
"Rrate",
runTime.timeName(),
mesh,
IOobject::NO_READ,
IOobject::AUTO_WRITE
),
mesh,
dimensionedScalar("Rrate", dimMass/dimVolume/dimTime, 0.0)
);

Then, i added this code in YEqn,

forAll(Y, i)
{
if (Y[i].name() != "CH4")
RR = reaction->R(Yi);
}

After wmake, it shows

YEqn.H:26:14: error: no match for ‘operator=’ (operand types are ‘Foam::volScalarField {aka Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh>}’ and ‘Foam::tmp<Foam::fvMatrix<double> >’)
Rrate = reaction->R(Yi);

Can you tell me how to do that? Thank you very much.