Theory of Turbulent Flow Between Parellel Plates 

 h = 6.35 cm 



c = 3.43 X 10"^ cm/sec ; ' ' ' ' : 

 Wq = 728 cm/sec (maximum mean velocity, from R^^) 



-r^ = 0.00295 (from [8], Fig. 19) 



^ ^ - T^ 4^ = 45.5 (from [8], Fig. 19; Fig. 8). 



7 = 1.400 ': ; " '" " 



a = 0.709 : ' - ■■ -.>; 



q = 0.33 : ■ V •' '.' '' 



Derived dimensionless parameters: ,' - 



R = 30,800 



o o ' „ _. 



/3 = v/ch = 0.69 ■ 10"^ ■ '' '' ; 



g/Roo - 45.5 



q = 1.40 - 10^ • ■ • 



CO = ^^(^^^) = 1120 f (this relates co to frequency f - Hz) 



Laufer (Fig. 27 [8]) shows the frequency spectrum reproduced as Fig. 2. 

 We would estimate a high-frequency cutoff at 



0)^, = 65 X 10^ 



fo = 58,000 Hz 



As indicated in Fig. 2 (dotted lines), this is not inconsistent with Laufer 's 

 data. 



An added "validation" for the high-frequency cutoff is the question of the 

 smallest size "eddies" that might be associated with the turbulent field. 



Let us consider the "wavelength" I associated with the high-frequency 

 cutoff. Because of the vector magnitude of x = a^ + S^, one would expect 

 approximately 



725 



