382 



FLOW 



FIGURE 24. Apparent coales- 

 cence of vapor bubbles within 

 cloud cavity; K = 0.28, 

 V^ = 14.8 m/s, Pco = 124.1 kPa, 

 a"= 3.25° + 1.55° sin ut. 



1.0 

 REDUCED FREQUENCY, K 



2.0 



2.S 



FIGURE 25. Variation in cloud cavitation with reduced frequency K and pitch amplitude a,. 



