Results 251 to 260 of about 2,960,271 (286)

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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Revisiting unresolved dynamic stall phenomena

38th Aerospace Sciences Meeting and Exhibit, 2000
In a series of dynamic stall tests, performed 1968 with a finite-span wing model having a NACA-0012 airfoil section, very unusual C,(a) characteristics were obtained by varying the Reynolds number as well as using fixed and free boundary layer transition.
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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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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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The effects of compressibility on dynamic stall

1st National Fluid Dynamics Conference, 1988
In this paper, typical computational predictions and experimental measurements of compressible flow past an airfoil at dynamic stall conditions are studied and compared to develop an insight into the effect of compressibility on dynamic stall. The dependency of the critical Mach number on airfoil leading edge curvature, camber, and angle of attack is ...
K.-Y. FUNG, L. CARR
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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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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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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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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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