Ignore interior section (or boundary) in CGNS mesh
 

Hi,

I am using a CGNS mesh which has a section (or boundary) with marker name "SURFACE_BODY_1_1_1D". This is an interior section. SU2 recognizes this section as a boundary. However, I am not defining this marker in the CFG file because there is not boundary condition associated with it. So, SU2 quits with the error:

My questions is: Can SU2 handle such an interior section?
In other words, can SU2 just ignore the section or boundary with the marker name "SURFACE_BODY_1_1_1D".

I would have preferred to remove the section from the CGNS file, but this does not seem possible as of now.

Any help or direction is much appreciated.

Thanks,
Mandar

Thanks for the question.
As the error message states, every boundary needs to have a defined boundary condition. Otherwise the solution behavior would be undefined, even if you were able to run the code without a boundary condition. Effectively, with the boundary there the mesh does not know how to connect the points on either side, and so it can't properly solve the problem.

If your desired behavior is for the code to treat that 'boundary' as just a part of the interior of the mesh, and it does not have any interior volume, then you should regenerate your mesh such that that boundary does not exist. There is an 'interface' boundary condition, however this requires two boundaries, not one, and is a more involved set-up that I would not recommend for what you are describing.

However, it also sounds from the name of the boundary that it is intended to be a solid wall, in which case you should specify it as an euler_wall (or other appropriate boundary) in the config file. If this boundary is a slip line (aka, extending from the trailing edge of an airfoil where you want to specify that the flow is parallel to that line in the wake), then you can set it as as symmetry condition.

Hi hlk,

Thanks for your reply.

The boundary in questions was not really a boundary. It was simply an interior line in the 2D mesh which resulted from the mesh generator and had a name associated with it.

Anyway, I was able to get around this problem by deleting that spurious line.

--Mandar

Marker = SURFACE_BODY_1_1_1D

I'm facing the same error now. Please let me know how did you delete the interior line generated in the mesh.

Hi,
you have to delete this in the mesh generator that you used to create the mesh.

Thanks for your reply. But I'm using Ansys Fluent Mesher, I can't really find a way to do so.

You can try setting that as MARKER_INTERNAL = SURFACE_BODY_1_1_1D

Fluent Mesher takes the cgns geometry as an input. You have to do the removal in the geometry, so before using Fluent Mesher. You can do this in SpaceClaim or another design tool.

Thanks for the input. I managed to delete the curve which was causing trouble.

Many thanks to everyone who contributed.

Can you please inform how did you do it ? as I am facing problem as you did.