113. INFINITELY WIDE STREAM INCIDENT NORMALLY ON A PLANE LAMINA. 



Let a steady uniform stream impinge perpendicularly on a fixed plane lamina of breadth 

 I and continue beyond it with two free boundaries; see Figure 183. 



From the symmetry, there will be a central streamline which is straight until it meets 

 the lamina at its center C, then divides and follows the lamina to its edges, from which each 

 half continues as a free streamline AJ or A'l', on which the constant velocity will be assumed 

 to be unity. The general method described in Section 110 is applicable, and the mathematical 



In^ 



^ a 





1 n- 









A' c 



t 





C" 



V 







C 



A 



\ 



/ 



A 



C 





-1 





1 





Figure 183 — Plate in a stream with wake behind it. See Section 113. 



281 



