Slip walls or Zero shear stress

[jpo]

Hello


I am trying to understand if is it reasonable to use "slip walls" or "zero shear stress" to model smooth walls.
I am working with turbulent air flows in ducts.

Please share your comments.

 

[jpo]

Are there materials that would qualify as "slip walls"?

For example, the pipe roughness of glass/drawn brass/copper pipe is 0.0015 mm. Is it wise to enforce "zero shear stress" on such wall?