the actual surface reasonably well over most of the section. At the local irregular- 

 ities, the fluctuations in the calculated pressure distribution approximately repre- 

 sented the potential flow pressure distribution of the measured blade section. 



5. The pressure fluctuations predicted by the potential flow model are probably 

 smoothed out in the real flow by the viscous boundary layer. At the leading edge, 

 where the boundary layer is thin, pressure fluctuations due to section irregularities 

 probably occur, and would greatly influence cavitation inception at the leading edge. 

 This effect emphasizes the importance of improving the detail geometry of model- and 

 full-scale propellers, especially at the leading edges. 



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