be moving toward positive y at velocity U. The relevant formulas may then be obtained from 

 those of Section 84 by substituting 6 = C, ^ = 0, c = a, a = n-/2. 



On the lamina itself 6' = 0, a' = a, x = a cos 77 by Equation [82c], hence, from 

 Equation [84f, g], q^ = fJ and 



9t = 



1 / r 



, Ux 



[86a] 



where the upper sign refers to the front face and the lower to the rear face. If F = i ^jialJ, 

 the velocity is finite at one edge. 



The flow net for F = is shown in Figure 138, in which the dotted ellipse is now to 

 be ignored. The arrows have reference to motion upward. 



The kinetic energy per unit length is, from Equation [841], 



1 a '^ 



[86b] 



The forces are as in the last section; see Reference 1, Article 71. 



Figure 138 - Flow net around a plane lamina moving perpendicularly 

 at velocity V with F = 0. 



207 



