The paper presents an experimental study concerning the thickness of t
he liquid films flowing gravitationally on rugose of non-rugose surfac
es. The rugosities used consisted in various diameter filaments longit
udinally applied on the flow surface. By processing the experimental d
ata, calculation relationship for the film thicknesses were obtained,
considering the rugosity diameter and distance between the filaments.
The experimental results were correlated and compared with the data go
t by other authors.