Recent Developments in Turbulence Management : Meeting Proceedings

Including papers on riblets, this book covers their practical applications to aircraft and to a model ship, near-wall coherent structure of boundary layer and effects of flow three-dimensionality. This volume also includes LEBUs (Large Eddy Break-Up devices), surface roughness, compliant surfaces and polymer additives, and more.

I. Riblets.- Experiments with a 1:4.2 model of a commuter aircraft with riblets in a large wind tunnel.- Heat transfer study of riblets.- Performances of internal manipulators in subsonic three-dimensional Flows.- High resolution conformal mesh computations for V, U or L groove riblets in laminar and turbulent boundary layers.- Coherent structures over a smooth and a triangular riblet drag reducing surface.- Some further experiments on riblet surfaces in a towing tank.- II. LEBUs.- Analytical and experimental study of energy density spectra of the outer region of a manipulated turbulent boundary layer.- Review: effect of the OLDs on near wall coherent structures; discussion and need for future work.- III. Surface Roughness.- Turbulent drag reduction of a d-type rough wall boundary layer with longitudinal thin ribs placed within the traverse grooves.- The correlation of added drag with surface roughness parameters.- IV. Compliant Surfaces.- The optimisation of compliant walls for drag reduction.- Nonlinear evolution of modes in the flow over compliant surfaces.- On conditions of modelling and choice of viscoelastic coatings for drag reduction.- Experimental investigation of one-layer viscoelastic coatings action on turbulent friction and wall pressure pulsations.- V. Polymer Additives.- The pulseless injection of polymeric additives into near-wall flow and perspectives of drag reduction.- Initial section of time-dependence of the Toms effect for solutions of poly (ethylene oxide).- Panel discussions.- List of Referees.- List of Participants.- Author Index.