refineMesh from a cellSet issue
 

Hello everyone,

I am trying to carry out a local refinement of a cylinderToCell cellSet inside a 3D hex mesh. I have tried both global and patchLocal coordinate system with just the tan1 and tan2 directions. With the global setting, I obtain severely non-orthogonal cells in 4 specific regions (2 on the leading edge, and 2 on the trailing edge of an airfoil). With the local setting, similar region of the mesh is affected, but the refinement does not complete and is terminated with an error: (almost) zero vector as direction for cell 0.
The patch specified in the patchLocalCoeffs is the surface of the foil. I've attached screenshots of both cases to illustrate the problem.

If I refine with all three directions (tan1 tan2 and normal), I don't come across this problem.

Any ideas?