[sosos]

Hi to all.

I am trying to simulate a flame out of a swirl burner. The figure attached shows the domain I am working on. By the way, for now, I am only interested on the outlet of the burner and not in what happens inside.

I used gmsh to create the mesh and import it to openFoam. The mesh consists of 2 circular surfaces which are supposed to be the outlet of the burner. So the burner consists of two outlets; the inner surface is the outlet where the flow only follows the x-direction and the outer surface is the outlet where the flow encounters the fins to create swirling movement. Finally, the box represents the atmosphere where the flame is supposed to develop.

For the surface where the flow comes with some swirling motion I would like to use the "swirlInletVelocity" BC but openfoam gives me an error message: "Essential entry 'value' missing" like it's working with the "fixedValue" type.

I am not what you can call an openFoam expert so I am a bit lost here. What do you think I should change to make it run? And do you think this is the best way to simulate a swirling flow?

Sorry if I am not clear enough, so please feel free to ask me for more information and thank you for your help.

[yppoonia]

Hello,
Did you find the solution to this?

[Светлана]

Can you post your {} block in which the type is set to 'swirlInletVelocity' - then someone can suggest how to modify it? Also post the complete error message.

[yppoonia]

This the error message I am getting

--> FOAM FATAL IO ERROR:
Essential entry 'value' missing

file: /home/yogesh/OpenFOAM/yogesh-7/run/t4/0/U.boundaryField.inlet_ch from line 24 to line 29.

From function Foam::fvPatchField<Type>::fvPatchField(const Foam::fvPatch&, const Foam:imensionedField<Type, Foam::volMesh>&, const Foam::dictionary&, bool) [with Type = Foam::Vector<double>]
in file /home/ubuntu/OpenFOAM/OpenFOAM-7/src/finiteVolume/lnInclude/fvPatchField.C at line 97.

FOAM exiting


and this is the block in 0/U

{
type swirlInletVelocity;
axis (0 0 0.004);
origin (0 0 -0.005) ;
axialVelocity constant 23.0;
radialVelocity constant 0.1;
tangentialVelocity constant 0.1;
}

I have swirling flow in an annular region. Do I have to include some filename in 0/U while using the derived fvPatchFields?

[Светлана]

Thanks - could you please post the complete contents of the '0/U' file here?

[ybapat]

Hello,


You need to provide entry like

value uniform (0 0 0);


Once simulation starts BC will calculate velocity value at the boundary.

[Светлана]

Thanks - I was looking for an example in the openfoam tutorials but did not find any with this type.

Does someone have a working tutorial case with this BC? It could be added to the official tutorials for this openfoam distribution.

[yppoonia]

Hello,

Originally Posted by ybapat

Hello,


You need to provide entry like

value uniform (0 0 0);


Once simulation starts BC will calculate velocity value at the boundary.

thank you, the problem is sorted now.