Ebook: Turbulence and Coherent Structures: Selected Papers from “Turbulence 89: Organized Structures and Turbulence in Fluid Mechanics”, Grenoble, 18–21 September 1989

In the last 25 years, one of the most striking advances in Fluid Mecha­ nics was certainly the discovery of coherent structures in turbulence: lab­ oratory experiments and numerical simulations have shown that most turbulent flows exhibit both spatially-organized large-scale structures and disorganized motions, generally at smaller scales. The develop­ ment of new measurement and visualization techniques have allowed a more precise characterization and investigation of these structures in the laboratory. Thanks to the unprecedented increase of computer power and to the development of efficient interactive three-dimensional colour graphics, computational fluid dynamicists can explore the still myste­ rious world of turbulence. However, many problems remain unsolved concerning the origin of these structures, their dynamics, and their in­ teraction with the disorganized motions. In this book will be found the latest results of experimentalists, theoreticians and numerical modellers interested in these topics. These coherent structures may appear on airplane wings or slender bodies, mixing layers, jets, wakes or boundary-layers. In free-shear flows and in boundary layers, the results presented here highlight the intense three-dimensional character of the vortices. The two-dimensional large­ scale eddies are very sensitive to three-dimensional perturbations, whose amplification leads to the formation of three-dimensional coherent vorti­ cal structures, such as streamwise, hairpin or horseshoe vortex filaments. This book focuses on modern aspects of turbulence study. Relations between turbulence theory and optimal control theory in mathematics are discussed. This may have important applications with regard to, e. g. , numerical weather forecasting.

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Content:
Front Matter....Pages i-xiii
Remarks on Turbulence Theory....Pages 1-13
Hydrodynamic visualization of organized structures and turbulences in boundary layers, wakes, jets or propeller flows....Pages 15-26
Front Matter....Pages 27-27
The emergence of characteristic (coherent?) motion in homogeneous turbulent shear flows....Pages 29-44
Generation of coherent structures in free shear layers....Pages 45-73
Use of the proper orthogonal decomposition in a plane turbulent mixing layer....Pages 75-90
On the Three-Dimensional Dynamics of Coherent Vortical Structures Forming in Free, Shear Flows....Pages 91-111
Visualizations of helium jets in air....Pages 113-124
Thermal striping : structures in interacting jets....Pages 125-138
Front Matter....Pages 139-139
Three-dimensional aspects of the organized motion in a turbulent boundary layer....Pages 141-157
Large eddy simulation of boundary layers with a step change in pressure gradient....Pages 159-174
Front Matter....Pages 175-175
Intermittent structure of dissipation in isotropic turbulence viewed from a direct simulation....Pages 177-189
The spatial structure of homogeneous turbulence at Reynolds Numbers around 1000....Pages 191-201
Wavelet analysis of fully developed turbulence data and measurement of scaling exponents....Pages 203-215
How Solenoidal can be the Lamb Vector in Turbulent Flow? Consequences and Implications....Pages 217-224
Front Matter....Pages 225-225
Bifurcations and bursting of streaks in the turbulent wall layer....Pages 227-251
The Dynamics of Organized Structures in the Axisymmetric Jet Mixing Layer....Pages 253-265
Instability of the rectangular duct flow and generation of the secondary flow....Pages 267-281
Front Matter....Pages 283-283
Vortex breakdown: a coherent transition trigger in concentrated vortices....Pages 285-302
Numerical simulation of vortex breakdown via 3-D Euler equations....Pages 303-320
Front Matter....Pages 321-321
The Coherent Vortices of Two-dimensional and Geostrophic Turbulence....Pages 323-342
Front Matter....Pages 321-321
Experiments On Forced, Quasi-Two-Dimensional Turbulence at Upwelling Fronts....Pages 343-353
Merging of two-layer baroclinic vortices....Pages 355-365
Transmission of acoustic waves through mixing layers and 2D isotropic turbulence....Pages 367-384
Front Matter....Pages 385-385
Spectra and correlation functions of surface layer atmospheric turbulence in unstable thermal stratification....Pages 387-412
Organized Structures in Strongly Stratified Flows....Pages 413-428
Fossil and Active Turbulence....Pages 429-448
Coherent Structures in Stratified Turbulent Shear Flows Deduced from Direct Simulations....Pages 449-468
Influence of a shear on a stably-stratified flow....Pages 469-487
Gravity wave patterns in the wake of a sphere in a stratified fluid....Pages 489-503
Front Matter....Pages 505-505
The compressible mixing layer....Pages 507-523
Numerical simulations of supersonic plane Couette flow instability....Pages 525-536
Reactive Scalar as a Tracer of Organized Structures in Turbulent Mixing Layers....Pages 537-550
Front Matter....Pages 551-551
Large-eddy simulation of MHD turbulent channel flow under a uniform magnetic field....Pages 553-567
Coherent Structures in MHD Turbulence and Turbulent Dynamo....Pages 569-584
Back Matter....Pages 585-626

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Content:
Front Matter....Pages i-xiii
Remarks on Turbulence Theory....Pages 1-13
Hydrodynamic visualization of organized structures and turbulences in boundary layers, wakes, jets or propeller flows....Pages 15-26
Front Matter....Pages 27-27
The emergence of characteristic (coherent?) motion in homogeneous turbulent shear flows....Pages 29-44
Generation of coherent structures in free shear layers....Pages 45-73
Use of the proper orthogonal decomposition in a plane turbulent mixing layer....Pages 75-90
On the Three-Dimensional Dynamics of Coherent Vortical Structures Forming in Free, Shear Flows....Pages 91-111
Visualizations of helium jets in air....Pages 113-124
Thermal striping : structures in interacting jets....Pages 125-138
Front Matter....Pages 139-139
Three-dimensional aspects of the organized motion in a turbulent boundary layer....Pages 141-157
Large eddy simulation of boundary layers with a step change in pressure gradient....Pages 159-174
Front Matter....Pages 175-175
Intermittent structure of dissipation in isotropic turbulence viewed from a direct simulation....Pages 177-189
The spatial structure of homogeneous turbulence at Reynolds Numbers around 1000....Pages 191-201
Wavelet analysis of fully developed turbulence data and measurement of scaling exponents....Pages 203-215
How Solenoidal can be the Lamb Vector in Turbulent Flow? Consequences and Implications....Pages 217-224
Front Matter....Pages 225-225
Bifurcations and bursting of streaks in the turbulent wall layer....Pages 227-251
The Dynamics of Organized Structures in the Axisymmetric Jet Mixing Layer....Pages 253-265
Instability of the rectangular duct flow and generation of the secondary flow....Pages 267-281
Front Matter....Pages 283-283
Vortex breakdown: a coherent transition trigger in concentrated vortices....Pages 285-302
Numerical simulation of vortex breakdown via 3-D Euler equations....Pages 303-320
Front Matter....Pages 321-321
The Coherent Vortices of Two-dimensional and Geostrophic Turbulence....Pages 323-342
Front Matter....Pages 321-321
Experiments On Forced, Quasi-Two-Dimensional Turbulence at Upwelling Fronts....Pages 343-353
Merging of two-layer baroclinic vortices....Pages 355-365
Transmission of acoustic waves through mixing layers and 2D isotropic turbulence....Pages 367-384
Front Matter....Pages 385-385
Spectra and correlation functions of surface layer atmospheric turbulence in unstable thermal stratification....Pages 387-412
Organized Structures in Strongly Stratified Flows....Pages 413-428
Fossil and Active Turbulence....Pages 429-448
Coherent Structures in Stratified Turbulent Shear Flows Deduced from Direct Simulations....Pages 449-468
Influence of a shear on a stably-stratified flow....Pages 469-487
Gravity wave patterns in the wake of a sphere in a stratified fluid....Pages 489-503
Front Matter....Pages 505-505
The compressible mixing layer....Pages 507-523
Numerical simulations of supersonic plane Couette flow instability....Pages 525-536
Reactive Scalar as a Tracer of Organized Structures in Turbulent Mixing Layers....Pages 537-550
Front Matter....Pages 551-551
Large-eddy simulation of MHD turbulent channel flow under a uniform magnetic field....Pages 553-567
Coherent Structures in MHD Turbulence and Turbulent Dynamo....Pages 569-584
Back Matter....Pages 585-626
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