Near-wall structure of three-dimensional turbulent boundary layers

1997 ◽  
Vol 23 (4) ◽  
pp. 335-340 ◽  
Author(s):  
K. A. Flack
Keyword(s):  
Boundary Layers ◽  
Three Dimensional ◽  
Turbulent Boundary Layers ◽  
Wall Structure ◽  
Near Wall

scholarly journals Recurrent motions within plane Couette turbulence

2007 ◽  
Vol 580 ◽  
pp. 339-358 ◽  
Author(s):  
D. VISWANATH
Keyword(s):  
Periodic Solutions ◽  
Couette Flow ◽  
Boundary Layers ◽  
Coherent Structures ◽  
Three Dimensional ◽  
Turbulent Boundary Layers ◽  
Transition To Turbulence ◽  
Good Resolution ◽  
Plane Couette Flow ◽  
Near Wall

The phenomenon of bursting, in which streaks in turbulent boundary layers oscillate and then eject low-speed fluid away from the wall, has been studied experimentally, theoretically and computationally for more than 50 years because of its importance to the three-dimensional structure of turbulent boundary layers. Five new three-dimensional solutions of turbulent plane Couette flow are produced, one of which is periodic while the other four are relative periodic. Each of these five solutions demonstrates the breakup and re-formation of near-wall coherent structures. Four of our solutions are periodic, but with drifts in the streamwise direction. More surprisingly, two of our solutions are periodic, but with drifts in the spanwise direction, a possibility that does not seem to have been considered in the literature. It is argued that a considerable part of the streakiness observed experimentally in the near-wall region could be due to spanwise drifts that accompany the breakup and re-formation of coherent structures. A new periodic solution of plane Couette flow is also computed that could be related to transition to turbulence.The violent nature of the bursting phenomenon implies the need for good resolution in the computation of periodic and relative periodic solutions within turbulent shear flows. This computationally demanding requirement is addressed with a new algorithm for computing relative periodic solutions one of whose features is a combination of two well-known ideas – namely the Newton–Krylov iteration and the locally constrained optimal hook step. Each of the six solutions is accompanied by an error estimate.Dynamical principles are discussed that suggest that the bursting phenomenon, and more generally fluid turbulence, can be understood in terms of periodic and relative periodic solutions of the Navier–Stokes equation.

Visualization of a mechanism for three-dimensional interaction and near-wall eruption

1999 ◽  
Vol 394 ◽  
pp. 193-203 ◽  
Author(s):  
C. V. SEAL ◽  
C. R. SMITH
Keyword(s):  
Turbulent Flow ◽  
Boundary Layers ◽  
Three Dimensional ◽  
Surface Interactions ◽  
Turbulent Boundary Layers ◽  
Hydrogen Bubble ◽  
Local Surface ◽  
Experimental Configuration ◽  
Dimensional Interaction ◽  
Near Wall

An experimental configuration has been found which allows detailed observation of three-dimensional vortex–vortex and associated vortex–surface interactions which appear similar to those observed in fully turbulent flow. Hydrogen bubble visualization illustrates a complicated intertwining, or braiding, of two initially co-rotating vortices. It is observed that the three-dimensional interactions of the braided vortices induces a pair of local surface-fluid eruptions reminiscent of the ‘bursting’ behaviour characteristic of the near-wall regeneration process of fully turbulent boundary layers.

A Review of Near-Wall Similarity Models in Three-Dimensional Turbulent Boundary Layers

1983 ◽  
Vol 105 (3) ◽  
pp. 251-256 ◽  
Author(s):  
F. J. Pierce ◽  
J. E. McAllister ◽  
M. H. Tennant
Keyword(s):  
Shear Stress ◽  
Wall Shear Stress ◽  
Boundary Layers ◽  
Force Measurement ◽  
Three Dimensional ◽  
Shear Velocity ◽  
Turbulent Boundary Layers ◽  
Velocity Relationship ◽  
Wall Shear ◽  
Near Wall

Eleven near-wall similarity models for three-dimensional turbulent boundary layers which have been identified in the literature are reviewed. Each model summary includes a brief review of its derivation, discusses limitations in the derivation, estimates the applicable y+ range, and compares differences among the models. This review of three-dimensional similarity models was developed as part of a larger study which tests the validity of ten of these different models by comparison with experimental data which includes the direct and simultaneous measurement of the local wall shear stress direction and magnitude in a three-dimensional turbulent flow. A direct force measurement of local wall shear stress is necessary to test the local wall shear-shear velocity relationship, τ0 = ρq*2, generally assumed in three-dimensional flows. This review is necessary to acquaint the reader with the similarities and differences among the models tested in companion papers since differences among some of the models are significant, particularly in the coordinate systems of the vector models.

Effects of Three-Dimensional Pressure Gradients on High-Speed Turbulent Boundary Layers

2021 ◽  
Author(s):  
Scott J. Peltier ◽  
Brian E. Rice ◽  
Ethan Johnson ◽  
Venkateswaran Narayanaswamy ◽  
Marvin E. Sellers
Keyword(s):  
Boundary Layers ◽  
High Speed ◽  
Three Dimensional ◽  
Turbulent Boundary Layers ◽  
Pressure Gradients
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