Is there any way to change unit other than scailing?
 

I've been working on full passage of turbine grid, and then just realized I imported the geometry in wrong unit, mm, which is supposed to be cm.

Since this is full passage of turbine, not sure if the scailing of geometry and blocking, and translatining a passage before copying it to full passage..
What I'm mostly worried about is that because of the tolerance problem, I'm afraid that there could be some kinda gap between passages if I scale them making the mesh quality bad.

If anyone knows how to change unit other than scailing, could you explain it?

no worries.
complete the mesh as you are doing, export to your solver mesh, import into pre and scale it there.

keep in mind, CFX typically works in SI meter unless you customize the solver units.

Thanks for your answer, mjgraf! :D