Internal cylinder flow: createPatch problem
 

Dear Foamers,
I am new to openFoam. Now I am trying to simulate internal cylinder flow with periodic boundaries.
1) I follow this cylinder case tutorial, https://sites.google.com/site/snappy.../cylinder-case,
and use open cylinder, right block to create meshes.
2) I run "autoPatch 75" and obtain the inlet and outlet patches.
3)When I run the solver, the following error occurs.
"face area does not match neighbour -- possible face ordering problem."
4) I run "createPatch", the following error occurs.
"Cannot find point in pts1 matching point coord in pts0 when using tolerance ...
Searching started from..."
5) To solve the problem, I increase "matchTolerance" in "createPatchDict".
When "matchTolerance" is set to be 0.1, Errors like that in step 4) disappear.

Do you think value of "matchTolerance" equal to 0.1 is too large?

Does anyone find a mistake in my proceedings?

Regards,
Meng