Since v and Y are available from the preliminary design calculations 

 2n 



1 

 k = 



P. = x y dx 



and 



x^ 1 v 2n y dx 



can also be precalculated in the preliminary design. Then the nondimensional thrust 

 and power coefficients are obtained in a conventional way: 



■if 



C T = ir ll p 2 - ¥ I (C L C0S *-S S 

 1 P S r H 



(45) 



1 



m(") 7. I 



^ , - ~- I r(C T sin (H-C cos cf)) dr 

 R 2 V 3 uA J L ° 



P tt „2 „3 ttX 



j p R V 



Z o . 



where T = propeller thrust 

 Q = propeller torque 

 <j) = pitch angle, i.e., 



+ a 



The efficiency of the propeller is given by 



C 

 r 



P 



20 



