11 



00,000 

 80,000 

 60,000 



40,000 



























































































































10,000 

 8000 

 6000 



4000 



2000 



1000 



^ 800 



600 

















































































































































































































































































:> 



5 200 



: 



: 































































































60 

 40 



20 



10 

 8 

 6 





















































































































































































































2 

 1 































































0.02 0.04 0.06 0.1 0.2 0.4 0.6 I 2 



Equivalent Radius r 9 in centimeters 



Figure 6 - The Variation of Reynolds Number with Size for Bubbles Rising 

 at their Terminal Velocity in Water at 67 P 



are both important in determining the shape and consequently the drag coeffi- 

 cient of the bubble. As the bubble size increases, the shape of the bubble 

 becomes flatter with a consequent rise in the value of the drag coefficient. 

 For a Reynolds number greater than 5000, surface tension plays a relatively 

 minor role in determining the shape of the bubble; hydrodynamic forces acting 

 on the bubble result in the spherical cap shape. 



A description of the shape and motion of the bubble as a* function of 

 bubble size is given in Table 1 for air bubbles rising at their terminal ve- 

 locity in water at 67° F. 



