How can I connect 2 blocks with a different grading?
 

Hi

In my mesh, I need to connect blocks where the cell-faces don't exactly fit. Sometimes the number of cells is different, sometimes the grading. Is there a way to do this? I was trying around for some time now, but didn't find a way.

Perhaps someone can help me?

Regards
Ghash

Ggi
 

Hi Gash,

have a look at the general grid interface (GGI) in OpenFOAM-1.5-dev, which provides a way to interpolate between non-matching cell-faces/patches. The 1.5-dev version also has a tutorial case: icoDyMFoam/mixerGgi

cheers,
Johannes

A sliding interface (called mergedPatchPairs in blockMesh) should also do the job for you.

Good luck,

Hrv

Is there a tutorial for version 1.6 that shows this? I'm having a similar problem with a wedge geometry; I have two blocks with different grid spacing that I want to merge, but I keep getting errors. If I try face matching as described in the User Guide, I get errors that there is an inconsistent number of faces between the two blocks. If I try tface merging by defining patches on the interface between the two blocks and putting the faces in the mergePatchPairs list at the end of the blockMeshDict file, I get errors that this, followed by a large amount of additional text:

Trying to specify a boundary face 4(3 4 5 3) on the face on cell 0 which is either an internal face or already belongs to some other patch.

Alan,
probably your error was about that :

When defining a face of a patch, the vertices of the neighbor blocks or patches must not have the same vertices number, you have to create double vertices, meaning same points but other vertices number.