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(Block 20 continued) 



the viscid-inviscld interaction between the thick stern boundary layer 

 and the external potential flow. The measured values of turbulence 

 intensity, eddy viscosity, and mixing-length parameters in the stern 

 region are found to be much smaller than those of a thin boundary 

 layer. An approximate similarity characteristic for the thick axi- 

 symmetric stern boundary layer is obtained when the measured mixing- 

 length parameters, the measured correlation length scales, and the 

 measured Taylor microscales are normalized by the square root of the 

 boundary-layer cross-sectional area instead of the local boundary layer 

 thickness. When this simple similarity hypothesis for the mixing 

 length and the displacement body is incorporated into the McDonnell 

 Douglas Corp., Cebeci-Smith differential boundary-layer method, 

 modified to consider the displacement body and wake, the theory predicts 

 very well the measured distributions of the mean velocity throughout 

 the entire stern boundary layer. The computation method developed 

 earlier was found to predict well the boundary layer on convex sterns 

 and is now found to apply equally well to the flow on inflected sterns. 



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