125 



0.5 0.6 07 08 09 10 



prediction of the thick boundary layer. Its ex- 

 tension to the wake is not altogether satisfactory 

 and this is attributed largely to the lack of a 

 systematic procedure for the description of the 

 velocity profiles in the near wake. This method 

 is ideally suited, however, for rapid calculations 

 to determine the state of the boundary layer in the 

 tail region for certain applications. 



ACKNOWLEDGMENTS 



This research was carried out under the sponsor- 

 ship of the Naval Sea Systems Command, General 

 Hydro-Mechanics Research Program, Sub-project 

 SR023 01 01, administered by the David W. Taylor 

 Naval Ship Research and Development Center, Contract 

 N00014-75-C-0273. The authors acknowledge the 

 assistance of Professor B. R. Ramaprian through 

 several stimulating discussions on the influence 

 of longitudinal surface curvature on turbulent 

 boundary layers. 



FIGURE 6(d). Wall shear stress. 



REFERENCES 



the data, this would appear to be desirable since 

 it would provide an extra equation for the length- 

 scale of the turbulence in addition to that for 

 its intensity. This would also enable the incorpo- 

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 recent work of Launder, Priddin and Sharma (1977) 

 and Chambers and Wilcox (1977) indicates that even 

 two-equation models, at least of the type available 

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In addition to the problem of turbulence models, 

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The representative calculations presented in 

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