Review—Advances in Three-Dimensional Turbulent Boundary Layers With Emphasis on the Wall-Layer Regions

1996 ◽  
Vol 118 (2) ◽  
pp. 219-232 ◽  
Author(s):  
J. P. Johnston ◽  
K. A. Flack
Keyword(s):  
Boundary Layers ◽  
Turbulence Modeling ◽  
State Of The Art ◽  
Measurement Techniques ◽  
Three Dimensional ◽  
Turbulent Boundary Layers ◽  
Wall Layer ◽  
The Other ◽  
Pressure Gradients ◽  
Low Speed Streaks

Current information concerning three-dimensional turbulent boundary layers is discussed. Several topics are presented including (i) a detailed description of eleven experiments published since 1990. In nine cases cross flows are controlled by pressure gradients imposed from the freestream, but in two cases the cross flows are wall-shear-driven. The other topics include (ii) an examination of state of the art in measurement techniques; (iii) a look at some issues and ideas in turbulence modeling; and (iv) an introduction to new work on the visualization and description of quasicoherent structures (high/low-speed streaks and turbulent vortices) in three-dimensional turbulent boundary layers.

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

Scaling of adverse-pressure-gradient turbulent boundary layers

1992 ◽  
Vol 238 ◽  
pp. 699-722 ◽  
Author(s):  
P. A. Durbin ◽  
S. E. Belcher
Keyword(s):  
Boundary Layer ◽  
Pressure Gradient ◽  
Boundary Layers ◽  
Turbulent Boundary Layers ◽  
Wall Layer ◽  
Small Range ◽  
Surface Shear Stress ◽  
Pressure Gradients ◽  
Mean Flow ◽  
The Mean

An asymptotic analysis is developed for turbulent boundary layers in strong adverse pressure gradients. It is found that the boundary layer divides into three distinguishable regions: these are the wall layer, the wake layer and a transition layer. This structure has two key differences from the zero-pressure-gradient boundary layer: the wall layer is not exponentially thinner than the wake; and the wake has a large velocity deficit, and cannot be linearized. The mean velocity profile has a y½ behaviour in the overlap layer between the wall and transition regions.The analysis is done in the context of eddy viscosity closure modelling. It is found that k-ε-type models are suitable to the wall region, and have a power-law solution in the y½ layer. The outer-region scaling precludes the usual ε-equation. The Clauser, constant-viscosity model is used in that region. An asymptotic expansion of the mean flow and matching between the three regions is carried out in order to determine the relation between skin friction and pressure gradient. Numerical calculations are done for self-similar flow. It is found that the surface shear stress is a double-valued function of the pressure gradient in a small range of pressure gradients.

The measurement of skin friction in turbulent boundary layers with adverse pressure gradients

1969 ◽  
Vol 35 (4) ◽  
pp. 737-757 ◽  
Author(s):  
K. C. Brown ◽  
P. N. Joubert
Keyword(s):  
Shear Stress ◽  
Skin Friction ◽  
Boundary Layers ◽  
Three Dimensional ◽  
Turbulent Boundary Layers ◽  
Pressure Gradients ◽  
Two Dimensional ◽  
Direct Measurements ◽  
Floating Element ◽  
Dimensional Boundary

This paper describes a floating-element skin friction meter which has been designed for use in adverse pressure gradients. The effects of secondary forces on the element, which arise from the pressure gradient, are examined in some detail. The limitations of various methods of measuring wall shear stress are discussed and the results from the floating element device are compared with measurements taken in a two-dimensional boundary layer using Preston tubes and velocity profiles. As it is planned to use the instrument later for direct measurements of the shear stress in three-dimensional boundary layers, the relevance of the instrument to this situation is also discussed.

Turbulent boundary layers subjected to multiple curvatures and pressure gradients

1993 ◽  
Vol 246 ◽  
pp. 503-527 ◽  
Author(s):  
Promode R. Bandyopadhyay ◽  
Anwar Ahmed
Keyword(s):  
Boundary Layer ◽  
Pressure Gradient ◽  
Boundary Layers ◽  
Turbulent Boundary Layers ◽  
The Other ◽  
Pressure Gradients ◽  
Two Dimensional ◽  
Internal Layers ◽  
Vortex Systems ◽  
Corner Vortex

The effects of abruptly applied cycles of curvatures and pressure gradients on turbulent boundary layers are examined experimentally. Two two-dimensional curved test surfaces are considered: one has a sequence of concave and convex longitudinal surface curvatures and the other has a sequence of convex and concave curvatures. The choice of the curvature sequences were motivated by a desire to study the asymmetric response of turbulent boundary layers to convex and concave curvatures. The relaxation of a boundary layer from the effects of these two opposite sequences has been compared. The effect of the accompanying sequences of pressure gradient has also been examined but the effect of curvature dominates. The growth of internal layers at the curvature junctions have been studied. Measurements of the Górtler and corner vortex systems have been made. The boundary layer recovering from the sequence of concave to convex curvature has a sustained lower skin friction level than in that recovering from the sequence of convex to concave curvature. The amplification and suppression of turbulence due to the curvature sequences have also been studied.

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