The paper is concerned with the application of the Dipprey (6) and Owen (7) methods of correlating data from large scale roughness working in the fully rough regime. An earlier paper (3) tested the methods for varying size of roughness, whilst the present one is concerned with effect of the shape of duct cross section.

In the present tests data from three different roughnesses on a flat surface and on the inner tube of an annulus have been correlated with reasonable success. Other data from an annulus and a flat surface are shown to correlate, but more results are required for circular tubes.