Results 261 to 270 of about 11,271 (298)

Modeling of leading edge vortex burst

AIAA Atmospheric Flight Mechanics Conference and Exhibit, 2001
The burst of leading edge vortex (LEV) is investigated by a modified quasi-cylindrical approximation (MQCA) for the sub-core of the vortex. By assembling LEV with the MQCA and evaluating the total pressure drop along the sub-core of LEV, a model for predicting the location of LEV burst is proposed.
Haiye Lou, X. Huang
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Interactions of a vortex with an oscillating leading edge

AIAA Journal, 1996
This study adresses the detailed structure of the interaction of an incident vortex with a leading edge that is oscillating at the frequency of the incident vortex street. Instantaneous streamline patterns and vorticity distributions allow characterization of the mechanisms of interaction as a function of the timing, or phase shift, of the incident ...
R. W. Jefferies, D. Rockwell
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A conceptual study of leading-edge-vortex enhancement by blowing

6th Fluid and PlasmaDynamics Conference, 1973
A conceptual wind-tunnel-test program has been conducted to verify that blowing a stream of highpressure air over a swept-wing surface in a direction roughly parallel to the leading edge enhances the vortex system. The blowing is shown to intensify the leading-edge vortex and thus delay the deleterious effects of vortex breakdown to higher angle of ...
R. G. Bradley, W. O. Wray
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A theory for the core of a leading-edge vortex

Journal of Fluid Mechanics, 1961
In the flow past a slender delta wing at incidence one can observe a roughly axially symmetric core of spiralling fluid, formed by the rolling-up of the shear layer that separates from a leading edge. The aim in this paper is to predict the flow field within this vortex core, given appropriate conditions at its outside edge.The basic assumptions are (i)
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The compressible inviscid leading-edge vortex

Journal of Fluid Mechanics, 1965
The conically symmetric solution of the Eulerian equations of an incompressible fluid obtained by Hall, thought to be descriptive of flow properties in a leading-edge vortex, is generalized to include the effects of compressibility.
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NEW TWISTS IN THE LEADING-EDGE VORTEX

Journal of Experimental Biology, 2004
![Figure][1] Insects aren't airplanes. If they flew like airplanes, they would fall right out of the sky because their wings are much too small. But since they flap their wings, they can generate a `leading-edge vortex', a rotating element of fluid along the front of the wing ...
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Leading edge vortex and shear layer instabilities

36th AIAA Aerospace Sciences Meeting and Exhibit, 1998
The stability of a leading edge vortex was studied using available flow visualization and velocity data. The development of a vortex can be envisioned to compose of three possible stages. During the initial stage, the shear layer and its associated vorticity immediately downstream from the apex coalesce to form a primary vortex core.
T. Ng, Doug Oliver
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Three-Dimensional Substructure in a Leading Edge Vortex

41st AIAA Fluid Dynamics Conference and Exhibit, 2011
High pitch rate manoeuvres have been studied in great depth in recent decades, in respect to rotor dynamic stall and, more recently, in understanding bird and insect flight with view to application in biomimetic micro air vehicles (MAVs). The flow topology arising from such unsteady airfoil movement is complex.
Abel-John Buchner, Julio Soria, Damon Honnery   +2 more
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On leading edge vortex and its control

16th Atmospheric Flight Mechanics Conference, 1989
A simple model for the leading edge vortex and a postulation for the existence of a critical vorticity concentration above which a stable leading edge vortex cannot be maintained were proposed. Using the model and postulation, various aspects of vortex control by blowing were discussed.
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Control of leading edge vortex breakdown by blowing

26th Aerospace Sciences Meeting, 1988
An investigation into the effects of using a jet of air to control the vortex breakdown position on a 70 degree delta wing is presented. The specific objectives focused on optimizing the blowing positions in terms of maximum lift increments obtained for minimum blowing rates.
K. VISSER, K. IWANSKI, R. NELSON, T. NG
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