Flow Visualization of Separation Bubble on a Circular Cylinder

1992 ◽  
pp. 307-311
Author(s):  
Y. Tomonari ◽  
M. M. Zdravkovich
Keyword(s):  
Circular Cylinder ◽  
Flow Visualization ◽  
Separation Bubble

The vortex-shedding process behind two-dimensional bluff bodies

1982 ◽  
Vol 116 ◽  
pp. 77-90 ◽  
Author(s):  
A. E. Perry ◽  
M. S. Chong ◽  
T. T. Lim
Keyword(s):  
Circular Cylinder ◽  
Flow Visualization ◽  
Vortex Shedding ◽  
Bluff Bodies ◽  
Two Dimensional ◽  
Closed Cavity ◽  
Time Exposure ◽  
Starting Flow ◽  
Visualization Techniques ◽  
Insight Into

Using a variety of flow-visualization techniques, the flow behind a circular cylinder has been studied. The results obtained have provided a new insight into the vortex-shedding process. Using time-exposure photography of the motion of aluminium particles, a sequence of instantaneous streamline patterns of the flow behind a cylinder has been obtained. These streamline patterns show that during the starting flow the cavity behind the cylinder is closed. However, once the vortex-shedding process begins, this so-called ‘closed’ cavity becomes open, and instantaneous ‘alleyways’ of fluid are formed which penetrate the cavity. In addition, dye experiments also show how layers of dye and hence vorticity are convected into the cavity behind the cylinder, and how they are eventually squeezed out.

A Note on the Effect of Short and Long Laminar Separation Bubbles on Desinent Cavitation

1981 ◽  
Vol 103 (1) ◽  
pp. 28-32 ◽  
Author(s):  
V. H. Arakeri ◽  
J. A. Carroll ◽  
J. W. Holl
Keyword(s):  
Flow Visualization ◽  
Viscous Flow ◽  
Critical Velocity ◽  
Film Flow ◽  
Separation Bubble ◽  
Sudden Change ◽  
Cavitation Number ◽  
The Body ◽  
Laminar Separation Bubble ◽  
Laminar Separation

Earlier desinent cavitation studies on a 1/8 caliber ogive by one of the authors (J. W. H.) showed a sudden change in the magnitude of the desinent cavitation number at a critical velocity. In the present work it is shown by means of oil-film flow visualization that below the critical velocity a long laminar separation bubble exists whereas above the critical velocity the laminar separation bubble is short. Thus the desinent cavitation characteristics of a 1/8 caliber ogive are governed by the nature of the viscous flow around the body.

scholarly journals VELOCITY VECTOR MEASUREMENTS OF THE OSCILLATORY FLOWS AROUND A CIRCULAR CYLINDER BY FLOW VISUALIZATION USING TRACER PARTICLES

1990 ◽  
Vol 10 (Supplement2) ◽  
pp. 151-154
Author(s):  
Kesayoshi HADANO ◽  
Takashi SAITOU ◽  
Nobuyuki MUNENO ◽  
Noriyoshi NAKAMURA ◽  
Katsumi MITSUNAGA ◽  
...  
Keyword(s):  
Circular Cylinder ◽  
Flow Visualization ◽  
Velocity Vector ◽  
Oscillatory Flows ◽  
Tracer Particles

Cavitation Inception on a Circular Cylinder at Critical and Supercritical Flow Range

1986 ◽  
Vol 108 (4) ◽  
pp. 421-427 ◽  
Author(s):  
A. Ihara ◽  
H. Murai
Keyword(s):  
Circular Cylinder ◽  
Separation Bubble ◽  
Circular Cylinders ◽  
Critical Flow ◽  
Laminar Separation Bubble ◽  
Supercritical Flow ◽  
Laminar Separation ◽  
Cavitation Inception ◽  
Rear Part ◽  
Axisymmetric Bodies

Cavitation tests were performed in the critical and supercritical flow range on circular cylinders with and without boundary layer trip. Mean and fluctuating static pressures were meausred on the smooth circular cylinder from θ = 0 to 180° and on the tripped surface at θ = 104 and 106° corresponding to tripping wire location α = 38 and 40 deg. Through these measurements it was found that cavitation that closely resembles bubble ring cavitation reported on axisymmetric bodies took palce in a reattachment region of the laminar separation bubble for the critical flow range where the laminar separation bubble was present. For the supercritical flow range where the laminar separation bubble disappeared, smooth cavitation with small irregular bubbles at its rear part took place at a location about 100° from the stagnation point.

Sign in / Sign up

Export Citation Format

Share Document