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Hi everybody, I want to per

Hi everybody,

I want to perform calculations for a square box, using simpleFoam, with flow from several different directions (one direction at a time). To perform calculations for flow coming from the "south east" direction, I need to have an inlet bc at both the south and the east boundary patches, and outlet conditions for the north and west boundary patches. For the upper boundary i use symmetry bc and the lower has a wall bc.
This setup gives me an error at execution, with a message telling me that my patch type is inconsistent with my boundary patch etc...
I've used this setup many times in Fluent, so I'm a little surprised it didn't work here. Does anybody know what I'm doing wrong?

/David

 hjasak April 26, 2005 14:18

Sorry for being blunt, but how

Sorry for being blunt, but how did you imagine that the code will allow you to specify an outlet boundary condition on a patch that you specified as a symmetry plane?

The patch is either a symmetry plane, in which case the b.c. for ALL variables is symmetryPlane, or it is not and symmetry plane and you can set up any boundary condition you like.

If you still don't see it, please take a piece of paper, draw the symmetry plane boundary and try to figure out how should the flow come out of it.

Enjoy,

Hrv

 eugene April 26, 2005 17:21

When you say "square box" do y

When you say "square box" do you mean a cube or a 2-D square?

Assuming you are referring to a cube with diagonal cross-flow parallel to the wall and symmetry plane, there is no reason why it should not work. Maybe you should post the entire error message?

Hi again, Sorry if I was uncl

Hi again,
Sorry if I was unclear, I meant a cube with cross diagonal flow. The error message is:
...
Create mesh for time = 0

--> FOAM FATAL IO ERROR : inconsistent patch and patchField types for
patch type symmetryPlane and patchField type fixedValue

file: /home/OpenFOAM/OpenFOAM/OpenFOAM-1.0.2/run/simpleBuilding/0/p::north from line 41 to line 43.

Function: fvPatchField<type>const fvPatch&, const Field<type>&, const dictionary &)
in file: /home/dm2/henry/OpenFOAM/OpenFOAM-1.0.2/src/OpenFOAM/lnInclude/newFvPat chField.C at line: 139.

FOAM exiting

The case works just fine when using just one inlet boundary and one outlet (the boundaries parallell to the flow are then set to symmetry).

Any ideas?
/David

 hjasak April 27, 2005 11:46

As I've answered above, you ha

As I've answered above, you have defined the patch type to be symmetryPlane and the boundary condition to be fixedValue, which is not allowed:

- if you want a symmetry plane, define the b.c. on p to be symmetryPlane

- if you want fixedValue, define the patch type to be "wall" or "patch".

Now read the error message again - if you think it is unclear, please let me know what you'd like it to say and I will change it.

Hrv