F,13 • STAGNATION POINT SOLUTION 



Stx, in the formula 



q^ = -St^p^UiK — K) 

 becomes [37]: 



for spheres. For cyhnders, the constant is 0.040. 



For an approximate calculation over the face of a sphere, the con- 

 stant 0.042 may be apportioned linearly with /3 to 0.030 for flat plates, 



0.010 



Stc 



0.005 



0.5 



x/D 



1.0 



Fig, F,13a. Heat transfer on the face of a sphere in air. Ma, = 3; Reo^ = 10^ 



and the ratios Pe/poo, Me/M=o, as well as /3 computed from Newtonian pres- 

 sure calculations and isentropic expansion from the stagnation region. 

 The heat transfer rate then becomes a maximum at about 40 degrees. 

 Fig. F,13a, F,13b, and F,13c show the heat transfer on the face of a 

 sphere in air with M«, = 3 and Rcd^ = p^oUD/n^ = 10^ 10^ and 10^ 

 respectively. Also shown in the figures are the variations of heat transfer 

 for completely laminar flow using Eq. 7-3b. It is seen that the maximum 

 turbulent heat transfer rate increases relative to the maximum laminar 

 rate as Reynolds number increases. 



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