Structure of Turbulence and Drag Reduction: IUTAM Symposium Zurich, Switzerland July 25–28, 1989

Front Matter....Pages I-XXVI
Front Matter....Pages 1-1
Turbulent Boundary Layer Structure: Progress, Status, and Challenges....Pages 3-22
A Review of Vortex Structures and Associated Coherent Motions in Turbulent Boundary Layers....Pages 23-50
Hairpin Vortices in Turbulent Boundary Layers: The Implications for Reducing Surface Drag....Pages 51-58
Production of Turbulence in Boundary Layers and Potential for Modification of the near Wall Region....Pages 59-68
Visualisation of the Organized Motion in a Turbulent Boundary Layer....Pages 69-75
Analysis of Experimental Data on Boundary Layer Pressure Fluctuations in Turbulent Pipe Flow....Pages 77-84
Behaviour of Separation Bubble with Different Roughness Elements at the Leading Edge of a Flat Plate....Pages 85-92
Organized Structures and Transition in the Near Field of a Plane Jet....Pages 93-100
Determination of Regular Structures in Turbulent Mixing Processes by Raman Scattering....Pages 101-108
Wall Layer Eruptions in Turbulent Flows....Pages 109-118
Non-Linear Coherent Mode Interactions and the Control of Shear Layers....Pages 119-127
Wavenumber-Frequency Spectral Densities of Turbulent Wall Pressure and Wall Shear Fluctuations....Pages 129-136
Quadrant Analysis and Instantaneous Momentum Transport—a Critical Review....Pages 137-144
Artificial Control of Turbulent Mixing Layers....Pages 145-152
Front Matter....Pages 153-153
Dynamics of Dilute Polymer Solutions....Pages 155-185
The Effect of Dilute Polymer Solutions on Viscous Drag and Turbulence Structure....Pages 187-200
Aspects of Mechanisms in Type B Drag Reduction....Pages 201-213
Change of Structures Close to the Wall of a Turbulent Flow in Drag Reducing Fluids....Pages 215-222
The Influence of Polymer Additives on the Coherent Structure of Turbulent Channel Flow....Pages 223-232
Interaction of Molecules and Turbulent Flow in Dilute Polystyrene Solutions....Pages 233-240
Front Matter....Pages 153-153
Λ-Shaped Vortices in Dilute Polymer Solutions....Pages 241-248
Wake Flows in Dilute Polymer Solutions....Pages 249-255
Drag Reduction Caused by the Injection of a Polymer Solution into a Pipe Flow....Pages 257-274
Large Eddies and Polymer Strings....Pages 275-281
Friction Drag Reduction by Injection of Polyethyleneoxide Solution in a Turbulent Boundary Layer Through Slot and Perforated Section....Pages 283-290
Front Matter....Pages 291-291
Drag Reduction in Surfactant Solutions....Pages 293-312
Turbulent Drag Reduction Versus Structure of Turbulence....Pages 313-340
Drag Reduction by Sand Grain Roughness....Pages 341-348
Effect of Wall Suction on the Transport of a Scalar by Coherent Structures in a Turbulent Boundary Layer....Pages 349-356
Flow Control by Suction....Pages 357-360
Inertial Interaction of Spherical and Fibre-like Solid Particles with Turbulent Flowing Liquids....Pages 361-368
Front Matter....Pages 369-369
Hydrodynamic Instability and Coherent Structures in Turbulence....Pages 371-397
Effect of Three-dimensional Surface Elements on Boundary Layer Flow....Pages 399-406
Interpretation of Polymer Drag Reduction in Terms of Turbulence Producing Eddies Close to the Wall....Pages 407-415
Active Turbulence Control in Wallbounded Flow Using Direct Numerical Simulations....Pages 417-425
Front Matter....Pages 427-427
Drag Reduction by Passive Devices—a Review of some Recent Developments....Pages 429-465
Relation Between Outer Structures and Wall-layer Events in Boundary Layers with and without Manipulation....Pages 467-474
Boundary Layer Manipulators at High Reynolds Numbers....Pages 475-482
Large-scale Turbulence Structures in a Manipulated Channel Flow....Pages 483-493
Analysis of the Wake of an Outer Layer Manipulator....Pages 495-502
Front Matter....Pages 427-427
Panel Discussions....Pages 585-610
Influence of an Acoustic Field on the Flow Structure Behind a LEBU in a Turbulent Boundary Layer....Pages 503-506
Analysis of the Structure of a Turbulent Boundary Layer, with and without a LEBU Using Light Sheet Smoke Visualizations and Hot Wire Measurements....Pages 507-515
The Effects of Longitudinal Roughness Elements and Local Suction upon the Turbulent Boundary Layer....Pages 517-524
Turbulent Drag Reduction by Nonplanar Surfaces — A Survey on the Research at TU/DLR Berlin....Pages 525-543
Drag Reduction in Pipes Lined with Riblets....Pages 545-551
Drag Reduction Mechanisms and Near-wall Turbulence Structure with Riblets....Pages 553-560
The Bursting Process over Drag Reducing Grooved Surfaces....Pages 561-568
Riblets in Internal Flows with Adverse Pressure Gradients....Pages 569-576
Experimental Investigation of Turbulent Boundary Layers Manipulated with Internal Devices: Riblets....Pages 577-584