create patch to obtain annular pipe
 

Hello,

My case consists of a circular pipe which I would like to make annular with a specified location of its center, not necessarily in the middle of the pipe. The hole in the pipe should be small and in a location which may or may not include cell centers.

Is there a way to create such a patch and take away cells if needed?

Any idea of how to proceed is appreciated!
Thanks
/NW