0133 Flow visualization of the flow over a two-dimensional wing for a MAV applications

Flow visualization, manometry, and laser-Doppler anemometry have been applied to approximately two-dimensional water flow around segmental baffles with baffle spacing/depth equal to 0.4, window cuts from 10 to 50 percent, and Reynolds numbers ranging from 600–10,500 in order to simulate important aspects relating to shellside flow in shell-and-tube heat exchangers. The main features of the flow (which is eventually periodic in the streamwise direction), development lengths, pressure loss coefficients, and mean and rms velocity distributions are presented.

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The vortex-shedding process behind two-dimensional bluff bodies

Journal of Fluid Mechanics ◽

10.1017/s0022112082000378 ◽

1982 ◽

Vol 116 ◽

pp. 77-90 ◽

Cited By ~ 176

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.

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Flow visualization studies of free convection laminar-to-turbulent transition along a heated vertical plate in water induced by two-dimensional forced disturbances

Wärme- und Stoffübertragung ◽

10.1007/bf01002759 ◽

1971 ◽

Vol 4 (1) ◽

pp. 25-31 ◽

Cited By ~ 2

Author(s):

P. Čolak-Antić ◽

H. Görtler

Keyword(s):

Free Convection ◽

Flow Visualization ◽

Vertical Plate ◽

Two Dimensional ◽

Laminar To Turbulent Transition ◽

Turbulent Transition

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Flow Visualization and Leakage Measurements of Stepped Labyrinth Seals: Part 2—Sloping Surfaces

Journal of Turbomachinery ◽

10.1115/1.2841196 ◽

1997 ◽

Vol 119 (4) ◽

pp. 844-848 ◽

Cited By ~ 4

Author(s):

D. L. Rhode ◽

J. S. Younger ◽

M. D. Wernig

Keyword(s):

Flow Visualization ◽

Leading Edge ◽

Test Facility ◽

Variable Geometry ◽

Two Dimensional ◽

Labyrinth Seals ◽

Leakage Resistance ◽

Water Test ◽

Sloping Surface ◽

Visualization Techniques

An experimental investigation was conducted to determine the geometry–leakage relationship for advanced, stepped labyrinth seals. A unique, variable-geometry water test facility was constructed and used to acquire leakage resistance measurements for two-dimensional, planar models. Flow visualization techniques were also used to assist in identifying and understanding the turbulence generating flow patterns. It was found that contoured surfaces and restrictor tooth leading-edge shapes of proper dimensions can be incorporated into the cavity geometry to reduce seal leakage. Specifically, the combination of a sloping surface and a curved surface on the rotor within the labyrinth cavity gave significant improvement.

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