What is a boundary patch?
 

Hi,

Can you help me to complete the two following sentences:
A PATCH is ...
A BOUNDARY PATCH is ...

I would like a proper definition to put it in a wiki for a newbie like me.
Till now I have found this in the user guide pag U-129:
"A patch is a list of face labels which clearly must contain only boundary faces and no internal faces."
So can we say that a patch MUST be a boundary patch and that you cannot have an "internal" patch?

Thank you in advance.

yes patch is boundary where we define BC's there.