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In the second method the velocity U(x) on the surface of the given 

 body is given directly as the solution of the integral equation 



ruuiyfw ds = 1 



Jo 2r 3 



where s is the arc length along the profile, 

 x is equal to x(s), and 

 2P is the perimeter of a meridian section. 



An approximate solution to this integral equation is 



U^x) = (1 + kj cos y(x) 



where k is the longitudinal virtual mass coefficient and y = arctan -^-. 

 U (x) is used to obtain a sequence of successive approximations by means of 

 the iteration formula 



U n+1 (t) - U n (t) + cos y (t)[l ~ f 1 ^- U n (x)ds] 



Here, also, the iterations are most conveniently carried out in terms of the 

 differences between successive approximations to U(x) which also furnish a 

 measure of the error in the integral equation. Two methods of carrying out 

 the iterations are again available, of which one is semi -graphical, the other 

 completely arithmetical. The latter technique is employed on the same example 

 as was used to illustrate the first method. 



