Propeller -Induced Appendage Forces 



.16-1 



,14 



.12 



Force 

 Thrust 



% 



.04 



,02- 



^ 



.6 



— I — 

 1.0 



1.2 



1.4 



Fig. 50 - Ratios of the induced axial and transverse forces 

 to the propeller thrust as a function of the advance ratio: 

 B = 0.05 



6. The induced forces at the higher harmonics are less than those at blade 

 rate, for propellers with the same number of blades. 



7. The induced forces at blade rate decrease as the number of blades is in- 

 creased, for the same value of thrust coefficient. 



8. The ratios of the induced appendage forces to the propeller thrust show 

 only a small dependence on the advance ratio. 



COMPARISON OF THEORY AND EXPERIMENT 



With the availability of the experimental results that have been presented 

 herein, comparisons can be made to determine if the experimental data verify 

 the conclusions indicated by this theory. Only limited data from Ref. 10 were 

 available at the inception of the theoretical study, for which certain limited com- 

 parisons could be obtained, and the additional work in Refs. 15 and 16 provided 

 more data for comparison purposes. Since the values of propeller thickness, 

 chord, loading, etc., were selected as representative for purposes of computa- 

 tion and illustration, no direct comparison can be made with the data in the 



225 



