Curvature Effects Of Three Dimensional Thick Stern Boundary Layers

Curvature Effects of Three-dimensional Thick Stern Boundary Layers

Thick boundary-layer equations, including the variation of the metric coefficients with distance normal to the surface, are solved from the nose to the tail of an elongated three-dimensional body. Iteration between potential and boundary-layer flow solutions is adopted to obtain a converged solution in the stern region. The complete procedure makes use of Keller's box numerical scheme in a non-orthogonal curvilinear coordinate system and an isotropic eddy-viscosity model for the Reynolds stress tensor in both streamwise and crosswise directions. The numerical method allows the calculation of flows in which the crosswise component of velocity cntains regions of flow reversal across the boundary layer. The inviscid pressure is determined by using the Hess-Smith method. The program is validated for an axisymmetric body, and then the calculations are compared with measurements for two three-dimensional bodies having elliptical transverse sections. Keywords: Thick turbulent stern flows; Longitudinal and transverse curvature effects; Turbulence modeling; and Eddy viscosity.

Three-Dimensional Turbulent Boundary Layers

The IUTAM Symposium on Three-dimensional Turbulent Boundary Layers was suggested by the Gesellschaft für Angewandte Mathe­ matik (GAMM) and sponsored by the International Union of theor­ etical and Applied Mechanics. The symposium was organized by H.H. Fernholz (Hermann-Föttinger-Institut für Thermo- und Fluiddynamik der Technischen Universität Berlin) and E. Krause (Aerodynamisches Institut der RWTH Aachen). After two success­ ful Euromech Colloquia on the same topic in Berlin 1972 and Trondheim 1975 the organizers felt that another meeting should be convened, this time with participants from inside and out­ side Europe. The aim of the symposium has been to bring together scientists who are actively engaged in boundary layer research, both ex­ perimental and theoretical. The scope of the meeting encompass­ ed incompressible and compressible three-dimensional turbulent boundary layers. Special emphasis was laid on economical cal­ culation methods, on measurements of fluctuating quantities and on measuring techniques designed for and applied success­ fully to three-dimensional boundary layers. From among thirty-four papers submitted for presentation, twenty­ six contributions of twenty-five minutes each were selected by the European mernbers of the Scientific Committee. Furthermore there were four invited lectures of forty-five minutes. Short discussions were held directly after each presentation with a long discussion period at the end of each day. The final dis­ cussion on the last day of the symposium was recorded on tape and is presented in a slightly shortened version as the last contribution in this volume.

Hydrodynamics in the Ocean Environment