Propeller -Induced Appendage Forces 



Figure 41 presents similar results with the thickness ratio of the propeller 

 doubled; it can be seen that the thickness contribution per se has also been 

 doubled but that the total force is not increased in proportion to the increase in 

 propeller thickness. Thus it is seen that the phase difference between the vor- 

 ticity and thickness contributions is a significant factor in determining the total 

 force magnitude. 



,18n 



.16 



.14 



.12 ■ 



I U2wR2 



,10- 



,08 - 



.06 - 



,04 



,02 - 



total 



vorticit 



thickness 



i 



-^Sr 



1.0 



1.2 



1.4 



Fig. 41 - Transverse force as a function of the advance ratio 

 for a three-bladed propeller: /3 = 0.05, N = 3, tg/2c - 0.10 



217 



