Hello Experts,
I have the following geometry obtained after topology optimization, imported from an STL file:

I want to smooth only some faces, as the circular faces are part of my design. Therefore, I need to exclude the following faces from the smoothing process:

However, using PolyMesh --> Smooth, produces the following result, which also smooth my circular faces:

My question is, for the attached STL file, how to leave the circular faces flat and with the original dimensions?
Kinds regards,
Francisco