Propeller -Induced Appendage Forces 



V = uR 



z^l 



-Vr 



Fig. 38 - Geometric relations between an appendage 

 and a propeller blade cascade 



For |xo + iyo - x| > the coth function can be represented in a series whose 

 nonsteady portion is given by 



dW 



V 



dZ 



iF' sp -(27rm/d)(Xo+iyQ-x) 



This expression is now generalized to a distribution of vorticity of magnitude 

 yp(Xp) dXp over each propeller blade chord of length 2c, with the quantities Xq 

 and Yo chosen as the coordinates of the reference propeller blade centroid: 



Xq = £(1 + 2^) , 



(1) 



209 



