On the Transition to Turbulent Convection 



Fig, 7, (x,t) photographs of convectlve flow. The position x 



through the tank is along the abscissa; the total width of the 

 photograph represents 48 cm through the fluid. The time t 

 is along the ordinate. The Prandtl niiinber is 57. 



(a) R = 28 Rj.; the total time is 17 minutes 



(b) R = 200 R^; the total time is 17 minutes 



(c) R = 33 5 R^; the total time is 15 minutes 



301 



