Smith 



Fig. 12 - Resolution of a flow into 



and circulatory components 



Flows About Bodies of Revolution 



If X is the distance parallel to the axis, 6 the angular measure around the 

 body starting from the top, and r the radial distance from the axis, it is clear 

 that a body of revolution will have three velocity-perturbation components v^p, 

 Vgp, and Vrp. Again referring to Fig. 12, it is clear that for the general angle- 

 of -attack condition we will have two basic onset flows Vco^ and v^y, but no cir- 

 culation. The Vc„^ flow is parallel to the axis and generates radial and axial 

 perturbations. The crossflow component V^^ generates perturbations in all 

 three directions, x, r, and 6. According to crossflow theory, there are then 

 five velocity perturbation components, as follows: 



\ 



v^ 



1 , 



V. 



\ 



v^ 



V, 



1 



V, 



V^ COS e V^ V„ cos ^ " ' V„ sin 



X y X y y 



The combined perturbation velocities in the three directions are: 



- 1 



V. 



1 cos a + 



V. 



cos 6 sin a 



1 I cos 6 sin a 



(16) 

 (17) 



v^ sin e 



1 sin 6? 



(18) 



For this problem only five charts are needed. Provided the bodies are not too 

 close together, the charts can be used to work out interference effects. An ex- 

 ample would be the determination of the effect of two hydrofoil struts upon each 

 other. The report (8) is written as a sort of manual. 



340 



