compared with the experimental measurements performed using individual tubes to 



3 21 

 a hub sensor made at IHI Ship Model Basin. ' 



The open-water performance was calculated and compared with experimental 

 results in Figure 10. The predicted K^ values are in excellent agreement with 

 experimental measurements. The predicted K values are about 5 percent greater 

 than the experimental values over the range of advance coefficients. 



The pressure distribution on the blade of Propeller MP 282 was calculated for 

 two different J values; J = 1.054 and J = 1.163. The pressure coefficients were 

 calculated on both the suction and the pressure sides at selected radii (r/R = 0.6, 

 0.7, 0.8, 0.9). 



In Figures 11 and 12, the experimental measurements and the predicted C are 

 compared at J = 1.054 and J = 1.163, respectively. The experimental measurements 

 were made at a Reynolds number, R = 1.9 x 10 . The calculated pressure coeffi- 

 cients are in good agreement with measurements on the pressure side except near 

 the leading edge, but generally overpredict the suction side pressure. The agree- 

 ment at the reduced J value is better than that at the increased J value. In 

 general, the predicted values are in satisfactory agreement with the experimental 

 measurements throughout the radius at the two different J values. 



In Figure 13, the oil-film test results reconstructed from the photographs in 



6 6 



Reference 21 are shown at two Reynolds numbers; 1.1 x 10 and 2.6 x 10 . The oil 



film illustrates the surface streamlines on both sides of the blade. At the 



reduced R condition, the flow patterns on the suction side have significantly 



reduced shear stress over the forward part of the blade and a clear separation 



occurs slightly past midchord. On the pressure side, reduced shear regions occur 



toward the leading edge and some indication of a leading-edge laminar separation 



bubble occurs at both Reynolds numbers. 



No surface flow patterns are presented in Reference 21 for the test R of 



6 ". 



1.9 X 10 . However, judging from the measured pressure coefficients shown in 



Figures 11 and 12, it is possible that separation occurred near 0.7 fraction of 



chord on the suction side and at the leading edge on the pressure side in the form 



of a bubble. Such separation would explain the suction peak on the pressure side 



near the leading edge and the pressure peak measured at 0.7 radius at 0.7 fraction 



of chord (measurements were not made at a similar chordwise position at other 



radii). It is further hypothesized that the suction side separation is a thin 



