Agreement is also fairly good at x/L = 0.954 and degrees. However, at x/L = 0,954 

 and angular positions 83, 86, and 90 degrees, the measured axial velocity components 

 are smaller than the predicted components, with flow reversal predicted at 83 and 86 

 degrees. Agreement inside the boundary layer is particularly poor. Since the eddy 

 viscosity model plays an important role in this region, it is essential to examine 

 the eddy viscosity model used for computing the thick three-dimensional stern 

 boundary layer. 



MEASURED TURBULENCE CHARACTERISTICS 

 The turbulence characteristics of the thick three-dimensional boundary layer 

 were measured using an "X" hot-film probe. An on-line computer was used to collect 

 data at a sample rate of 1024 data values in 8 sec. The root-mean-square values of 

 turbulence velocity were recorded at each probe position and the eddy viscosity and 

 mixing length values were computed from the measured Reynolds stresses and the 

 measured mean velocity profiles. 



MEASURED REYNOLDS STRESSES 



The distribution of the Reynolds stresses -u ^v ' , -u'w' u'' , vj* , and Wq 



xnxDxn 



represent the turbulence characteristics in the thick boundary layer. The mean- 



~'72. ^2 



square turbulent velocity fluctuations u'' in the axial direction and v^ in the n^ 



direction, and the Reynolds stress -u'v' were measured with the "X" hot-film probe 

 ' ^ X n 



elements alined vertically. The probe elements were rotated 90 degrees to the hori- 



'/i 



zontal position to measure both the turbulent fluctuation Wg in the direction and 



the Reynolds stress -u w„. Linear interpolation was used to approximate Wg 



-u'w' at the same off-body positions as the data measured in the vertical direction. 



x 6 

 All measured values of the turbulent fluctuations and the measured Reynolds stresses 



are given in Tables 3 through 9. 



The nondimensionalized distributions of the measured turbulent fluctuations 



■2,„ J -2 



' u' /U . ' v' /U , and ' w' /U and Reynolds stress -100 u v /U at selected 

 xo no DO xno 



locations along the model, are shown in Figures 9 through 13. As can be seen 



13 



