Hollow Cylinder mesh region
 

Hello everyone,

I have a geometry like the one I've attached in the link, and I have to create a hole in the middle of the internal pipe. This geometry is inserted in a duct.
The problem is I have created a mesh region called fluid inside the duct and a second region called solid that corresponds to my stl. Is it possible to create a new mesh region called, for example, copper, related to the internal hole in the cylinder? And if yes, any idea of how to proceed using snappyhexmesh?

Thanks

Luca
https://ibb.co/tcc6kPz


If the image does not work, this is the direct link https://ibb.co/tcc6kPz