How to mirror two boundaries for cyclic patches?
 

Hi everyone,

I am new in meshing with blockMesh/snappyHexMesh and I am having trouble with achieving a mesh with 100% matching surfaces on two cyclic boundaries. Can anyone tell me what's the best way to mirror two meshed surfaces using Open Source software (preferably blockMesh/snappyHexMesh)? The surface area of the boundaries is the same, the created cell number (and node positions) is just different. My domain exists as a STEP/STL/OBJ file.

Thank you and best regards,

Frank Ubber

What you are asking is a difficult proposition. Besides defining the cyclics as boundaries with more refinement and aligning your mesh symetrically, these isn't a whole lot you can do. You can always reduct the matching tolerance ;)

So, how are meshes for use with cyclic patches usually made since you need a perfect patching partner face?

Well, it doesn't have to be 100% perfect, but it helps with the results. To do 100% matching you need to use a tool like blockMesh or similar that can create the faces explicitly based on your input. Also using binary format in your input files helps, since you can keep more precision.