[jst04004]

I am trying to run a simple simulation using the interFoam solver, but get the error message
patch type 'patch' not constraint type 'empty'
for patch Group_4 of field p_rgh in file......0/p_rgh


Group_4 is the front and back sides of my two dimensional simulation. Its a simple geometry, triangular wedge extruded for use with the interFoam solver. I know that I should be using the empty condition but don't know what to do from here. Any suggestions? I am thinking I just need to create the geometry again to make sure there is not some other problem going on, but thought I would throw an ear out for any help. Thanks!

[pbryant]

If the wedge shape means that this is an axisymmetric geometry, then you will need "wedge" type patches grouped separately into those in front and back. I would also advise you to run checkMesh.
Paul

[jst04004]

I ran check mesh and everything was fine. Tried changing from empty, but that didnt work either. The geometry was created using a 2D program, then changed over to a .gambit, then to foam. when doing so group_4 and group_5 are the front and back, and from all the documentation I have seen they should be set to empty for the 2d simulation. Here is the error:

--> FOAM FATAL IO ERROR:

patch type 'patch' not constraint type 'empty'
for patch Group_4 of field p_rgh in file "/home/jst04005/OpenFoam/Mud/Mud1/0/p_rgh"

file: /home/jst04005/OpenFoam/Mud/Mud1/0/p_rgh::boundaryField::Group_4 from line 49 to line 49.

From function emptyFvPatchField<Type>::emptyFvPatchField
(
const fvPatch& p,
const Field<Type>& field,
const dictionary& dict
)

in file fields/fvPatchFields/constraint/empty/emptyFvPatchField.C at line 100.

FOAM exiting





and here is the p_rgh file:


--> FOAM FATAL IO ERROR:

patch type 'patch' not constraint type 'empty'
for patch Group_4 of field p_rgh in file "/home/jst04005/OpenFoam/Mud/Mud1/0/p_rgh"

file: /home/jst04005/OpenFoam/Mud/Mud1/0/p_rgh::boundaryField::Group_4 from line 49 to line 49.

From function emptyFvPatchField<Type>::emptyFvPatchField
(
const fvPatch& p,
const Field<Type>& field,
const dictionary& dict
)

in file fields/fvPatchFields/constraint/empty/emptyFvPatchField.C at line 100.

FOAM exiting





Thanks for your help. I really appreciate it.

[jst04004]

to avoid confusion I forgot to mention that group_5 (the back) was mapped to group_4 (the front). That is why you only see info for group_4. This approach has worked in other geometries so not sure why it is giving me trouble now.

[pbryant]

I'm still not clear about your geometry. Usually a wedge shape is used when there is rotational symmetry about some axis in which case you need front and back wedge patches. If you were using blockMesh, you would then have entries like "wedge Group_4 ( (# # # #) (# # # #) ... )" in your patches list in blockMeshDict. If however this is a translational symmetry case that just happens to be wedge shaped, then you can eliminate all mention of these patches in blockMeshDict and also in the files in directory "0" and they will default to type empty. I dont have any experience outside of blockMesh so perhaps someone else can advise if this post is of no help.
Paul

[jst04004]

The geometry is simple. A right triangle, the 90' corner in top left, the hypotenuse sloping at .2, The coordinates for the vertices are (0,0), (0,6), (30,6). The left wall is set to inletOutlet, the top to atmosphere, and the slope to slip. I think my best bet is just to start over (luckily its not too complicated a setup) and be extra careful this time. Thank you very much for your help. I will post again if I experience the same problem again. You have been very helpful pbryant!

[billynoe]

group_4 and group_5 are the front and back, and from all the documentation I have seen they should be set to empty for the 2d simulation. Here is the error:

If you want a wedge these should be "wedge" types and you will also need a symmetry plane between them check out this utility add on. it works on foam 1.7.1 for sure.