Results 271 to 280 of about 105,600 (307)

Effects of Dynamic Stall on SWECS

Journal of Solar Energy Engineering, 1982
A study of dynamic stall is presented in order to define its influence on the airfoil force and moment coefficients so that these effects can be included in the calculation of small wind energy conversion system (SWECS) loads and responses. A review of past work indicates that semiempirical methods are best suited to SWECS requirements. A definition of
R. B. Noll, N. D. Ham
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Flight dynamics and control in relation to stall

2012 American Control Conference (ACC), 2012
Control of fixed-wing aircraft at high angles of attack is particularly challenging. In this case, aerodynamic forces can be subjected to strong variations, among which stall is certainly the most critical. This paper tackles flight dynamics and control for aerial vehicles subjected to the stall phenomenon.
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Some Measurements on Dynamic Stall

Journal of Aircraft, 1974
Details of a flow oscillation device and of force and moment measurements on a 2 ft chord twodimensional NACA 0012-64 airfoil in the oscillating flow and oscillated in pitch in a steady flow through stall are presented. Results indicate that both methods give essentially the same description of the dynamic stall process.
A. G. Parker, J. Bicknell
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A Phenomenological Model of Dynamic Stall

SAE Technical Paper Series, 2002
<div class="htmlview paragraph">Dynamic stall has been the subject of much research but there is still some uncertainty about several aspects. Almost all research to date has involved experiments or computational fluid dynamics, both, in essence, trying to duplicate the phenomena. The present research takes a different tack by trying to develop a
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Analysis of the onset of dynamic stall

AIAA Journal, 1992
The dynamic stall characteristics of several airfoils have been investigated to assess the effects of compressibility, unsteadiness, and airfoil geometry on the onset of dynamic stall. For the purpose of understanding the physical phenomena in the range of low reduced frequency of practical importance, it is found that the flow before the onset of ...
Jeffrey M. Currier, K.-Y. Fung
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Shock-induced dynamic stall

21st Aerospace Sciences Meeting, 1983
At freestream Mach numbers above M= 0 3 shock/boundary layer interaction begins to complicate the unsteady airfoil stall characteristics The present paper shows how theoretical relationships can be developed for the interdependence between unsteady and steady characteristics to provide the means whereby the shock induced dynamic stall characteristics ...
L. E. Ericsson, J. P. Reding
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Toward dynamic separation without dynamic stall

Experiments in Fluids, 1988
The concept of vorticity separation without dynamic stall is illustrated by flow visualization. A small airfoil with a rotating nose, originally built for the demonstration of static stall control, was placed in a wind tunnel and dynamically pitched. The flow around the airfoil during pitch was successfully visualized and filmed.
P. Freymuth, S. Jackson, W. Bank
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Analysis of Dynamic Stall using Dynamic Mode Decomposition Technique

31st AIAA Applied Aerodynamics Conference, 2013
Dynamic mode decomposition is applied to investigate the unsteady flowfield around a pitching airfoil. The extracted flow structures are termed as dynamic mode decomposition modes. Analyses are performed for both attached flow and dynamic stall cases. Initially, flowfield data generated from numerical simulations are investigated.
Mariappan, Sathesh, Gardner, Anthony Donald, Richter, Kai, Raffel, Markus   +3 more
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Control of Compressible Dynamics Stall Using Microjets

Volume 2: Symposia, Parts A, B, and C, 2003
Control of the dynamic stall process of an NACA 0015 airfoil undergoing periodic pitching motion is investigated experimentally in a high-speed wind tunnel facility. Multiple microjet nozzles distributed uniformly in the first 15% chord from the airfoil’s leading edge are used for the control. Point Diffraction Interferometry (PDI) technique is used to
Shih, C., Beahn, J., Krothapalli, A., Chandrasekhara, M.S.   +3 more
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A computational study on the dynamic stall of a flapping airfoil

16th AIAA Applied Aerodynamics Conference, 1998
The dynamic stall boundaries of a NACA 0012 airfoil oscillating in either the pure plunge mode or in the combined pitch and plunge mode is computed using a thin-layer Navier-Stokes solver. Unsteady flowfields are computed at the free-stream Mach number of 0.3, the Reynolds number of 1 • 10, and the Baldwin-Lomax turbulence model is employed.
Tuncer, Ismail, Walz, Ralf, Platzer, Max F.   +2 more
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