Propeller -Induced Appendage Forces 



,020 



,015 - 



.010 



.005 



total 



vorticity 



thickness 



■V 



.6 



1.0 



1.2 



1.4 



Fig. 45 - Second-harmonic axial force as a function of 

 the advance ratio' far a two-bladed propeller: /3 = 0.05, 



N = 2, m = Z .. , ,. 



,020 -I 



,015 



^ U2„RJ 



.010 



,005 - 



total 



vortici 



thickness 



.6 



.8 



1.0 



1.2 1.4 



Fig. 46 - Blade -rate axial force as a function of 

 the advance ratio for a four-bladed propeller: 



p = 0.05, N = 4, m = 1 



221 



