Formation of Vortex Street in Laminar Boundary Layer

1980 ◽  
Vol 47 (2) ◽  
pp. 227-233 ◽  
Author(s):  
M. Kiya ◽  
M. Arie
Keyword(s):  
Boundary Layer ◽  
Shear Flow ◽  
Laminar Boundary Layer ◽  
Solid Wall ◽  
Vortex Sheet ◽  
Vortex Street ◽  
Bluff Bodies ◽  
Uniform Shear ◽  
Uniform Shear Flow ◽  
Vortex Patterns

Main features of the formation of vortex street from free shear layers emanating from two-dimensional bluff bodies placed in uniform shear flow which is a model of a laminar boundary layer along a solid wall. This problem is concerned with the mechanism governing transition induced by small bluff bodies suspended in a laminar boundary layer. Calculations show that the background vorticity of shear flow promotes the rolling up of the vortex sheet of the same sign whereas it decelerates that of the vortex sheet of the opposite sign. The steady configuration of the conventional Karman vortex street is not possible in shear flow. Theoretical vortex patterns are experimentally examined by a flow-visualization technique.

scholarly journals Laminar Boundary Layer Separation in a Uniform Shear Flow

1973 ◽  
Vol 16 (99) ◽  
pp. 1289-1300 ◽  
Author(s):  
Masaru KIYA ◽  
Jun-ichi NISHIYAMA ◽  
Mikio ARIE
Keyword(s):  
Boundary Layer ◽  
Shear Flow ◽  
Laminar Boundary Layer ◽  
Boundary Layer Separation ◽  
Layer Separation ◽  
Uniform Shear ◽  
Uniform Shear Flow

An Analysis of Uniform Shear Flow Past a Porous Plate Attached to a Plane Surface

1980 ◽  
Vol 102 (2) ◽  
pp. 160-165 ◽  
Author(s):  
M. Kiya ◽  
M. Arie ◽  
K. Koshikawa
Keyword(s):  
Boundary Layer ◽  
Shear Flow ◽  
Velocity Profile ◽  
Boundary Layer Thickness ◽  
Plane Surface ◽  
Porous Plate ◽  
Source Model ◽  
Uniform Shear ◽  
Uniform Shear Flow ◽  
Layer Velocity

The wake-source model of Koo and James was extended to the case of a two-dimensional porous plate attached to a plane surface along which a turbulent boundary layer developed. The approaching stream is replaced by a uniform shear flow of linearly-varying velocity profile such that the height of the plate is much smaller than the boundary-layer thickness. The theory requires as input the pressure-drop coefficient of the porous plate and the boundary-layer velocity profile at an appropriate location upstream of the plate.

On the pressure induced by the boundary layer on a flat plate in shear flow

1964 ◽  
Vol 19 (1) ◽  
pp. 1-10 ◽  
Author(s):  
Alar Toomre ◽  
Nicholas Rott
Keyword(s):  
Boundary Layer ◽  
Shear Flow ◽  
Flat Plate ◽  
Flow Problem ◽  
Leading Edge ◽  
Fourier Integral ◽  
Pressure Gradients ◽  
Uniform Shear ◽  
Uniform Shear Flow ◽  
Lateral Extent

The problem solved is that of the interaction between a laminar boundary layer on a semi-infinite flat plate and an oncoming shear flow of finite lateral dimensions bounded by uniform irrotational flow extending to infinity. The pressures along the plate and upstream of the same are deduced (to a linearized approximation) in the form of a Fourier integral based on the solution of a simpler periodic flow problem. It is found that while the assumption of an infinite, uniform shear flow gives asymptotically correct interaction pressure gradients on the plate near the leading edge, the pressure level even there (compared to upstream infinity) is strongly influenced by the boundedness of the external shear. At distances from the leading edge which are large compared to the lateral extent of the shear flow, the pressure gradients along the plate are shown to be vanishingly smaller than in the infinite shear case.

Development of the boundary layer at a free surface from a uniform shear flow

1966 ◽  
Vol 25 (1) ◽  
pp. 87-95 ◽  
Author(s):  
Simon L. Goren
Keyword(s):  
Boundary Layer ◽  
Mass Transfer ◽  
Free Surface ◽  
Shear Flow ◽  
Surface Velocity ◽  
Cube Root ◽  
Two Dimensional ◽  
Uniform Shear ◽  
Uniform Shear Flow ◽  
Capillary Jets

The development of the boundary layer accompanying the formation of a free surface at y′ = 0, from the two-dimensional uniform shear flow u′ = ωyω, is discussed. The analysis shows that the surface velocity and surface position vary as the cube root of the distance downstream, while the mass-transfer coefficient varies inversely as the cube root of this distance. It is shown how these may be applied to the formation of capillary jets.

Sign in / Sign up

Export Citation Format

Share Document