A,ll • INFLUENCE OF TURBULENCE 



the intensity and scale of turbulence and not on the two properties 

 separately. 



Fig. A, 11a shows the critical Reynolds number of a sphere plotted as 

 a function of the Taylor turbulence parameter [4I] and Fig. A, lib shows 

 the location of transition on an elliptic cylinder as a function of the same 



0.12 



Ue VL/ 



0.08 



0.04 



0.8 1.2 1.6 2.0 2.4 



2.8 



Fig. A, 11a. EflFect of intensity and scale of free stream turbulence on the critical 

 Reynolds number of spheres. L = scale of turbulence, D = diameter of sphere. 



4.5 



X, in. 



5.0 5.5 



6.0 



0.08 



0.06 



u'/D\i 



UeVL/ 



0.04 



0.02 



1.0 



1.2 1.4 



x/D 



1.6 



Fig. A, lib. Effect of intensity and scale of free stream turbulence on transition on 

 an elliptic cylinder. L = scale of turbulence, D = length of minor axis of elliptical 

 section. 



parameter [34]. This theory accounts for the influence of stream turbu- 

 lence when the turbulence is greater than about two tenths of one per cent. 

 Experiments on a flat plate with zero pressure gradient were made by 

 Hall and Hislop [42] in turbulent air streams behind two square-mesh 

 screens. In this case there was Kttle overlap between the results for the 



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