[EHo]

Hi all,

I'm trying to solve a falling film flow (free surface flow -> interTrackFoam) where the liquid film is cooled at the wall (wall is neglected and cooling flow is directly attached).

What I've done so far:
- I've already solved the isothermal flow with interTrackFoam (1.6-ext)
- I've already solved the conjugated heat problem with prescribed trivial velocity profiles with conjugateHeatFoam
- now I wanted to combine both solvers but it seems that the mesh generator cannot handle regionCoupling!?

Selecting motion solver: laplaceFaceDecomposition

--> FOAM FATAL ERROR:
Unknown faceTetPolyPatchFaceDecomp type genericPatch. Valid faceTetPolyPatchFaceDecomp types are :

7
(
wall
processor
wedge
patch
empty
ggi
symmetryPlane
)

Does this make sense or is there something wrong with my code? What else can I do?

regards
Ernst

[diego_angeli]

Hello Ernst,
first of all congratulations for having performed such a challenging simulation (the isothermal free falling film!
I am about to tackle the problem of a free-falling annular jet with interTrackFoam and it would be great to know some details about how you managed to set BCs for the grid motion.

Before trying to simulate complex cases, I wanted to perform a simpler computation: the free-surface flow inside a rotating cylindrical vessel.
I'm making it 2D with an axisymmetric wedge geometry.
I already solved the closed cylinder case with simpleFoam and all was OK (with wedge BCs): I obtained a fair taylor-couette-type flow with sufficiently low rotational velocities.
But when I come to interTrackFoam, it seems that the rotation velocity in the third dimension does not propagate at all into the fluid.
Plus, an instability is triggered at some time that makes the freesurface solver "explode".
Any clue anyone about that?

As for your heat transfer problem, wouldn't it be easier to integrate only the energy equation in the interTrackFoam solver? I will have to do that too, maybe we can exchange some information about the process.

Thanks a lot

Diego

[kathrin_kissling]

Hi EHO,

it seems theres something wrong with your boundary condition set up. Since you are using the interTrackFoam the mesh on the surface needs to be updated. This is implemented for wall, ... (the ones you see in your error) I think you try to solve for another boundary condition. Could you post the constant/boundary file and the boundary files where the interface is described?

Best

Kathrin

[EHo]

Thank you for your replies and sorry for the delay, but I was out for vacation.

@ Diego: Sorry, no idea for your particular problem, haven't seen something similar in my simulations.

The implementation of the energy-equation to interTrackFoam is easy but unfortunately not sufficient. The challenge is the boundary condition to at the wall to model a conjugate heat problem.

@ Kathrin: Due to the combination with conjugateHeat, I have to define the wall as a "regionCoupling" boundary. Obviously this type of boundary cannot be handled by the mesh solver laplaceFaceDecomposition.

Summary: The energy equation works within interTrackFoam for example with an isothermal wall (Dirichlet) or const. heat flux (Neumann). But how to implement the conjugate heat?

Best
Ernst

[akidess]

Ernst, have you had any luck with this?