B,14 • COMPARISON BETWEEN EXPERIMENTS AND THEORIES 



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ulu 



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10 



M. 



Fig. B,14a. Compressibility effect on turbulent skin friction (experimental). The 

 experimental data are plotted according to [18,29,32,34,38,39,42,62,63]. The curve is 

 drawn according to Eq. 13-9, with a viscosity-temperature coefficient of 0.75. 



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u 



Fig. B,14b. Variation of skin friction with Reynolds number. C/ = average skin 

 friction coefficient. Re^ = peUe/iJLe, Reynolds number based on the free stream. The 

 experimental data are drawn from [29,32,33,66] for the free stream Mach number 

 Me = 0.81 — 3.6. The theoretical curves (Me = — 3.6) are plotted according to 

 Eq. 13-11, for n = 2.58, A = 0.455, a = 0.75. 



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