Author: J. M. SimmonsPublisher:
ISBN:
Category : Aerofoils
Languages : en
Pages : 10
Book Description
Experimental Investigation of Incompressible Flow Past Airfoils with Oscillating Jet Flaps
Author: J. M. SimmonsPublisher:
ISBN:
Category : Aerofoils
Languages : en
Pages : 10
Book Description
Experimental Investigation of Incompressible Flow Past Jet Flapped Airfoils
Author: Carl Mark TankersleyPublisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 115
Book Description
Experiments were conducted in low-speed wind tunnel to investigate the aerodynamic characteristics of an airfoil with a jet flap deflected at ninety degrees, in and out of ground effect. These tests consisted of detailed static pressure measurements on the airfoil, and helium bubble flow visualization studies of the resulting flow patterns. Substantial agreement was obtained with previous experiments conducted in England. (Modified author abstract).
Workshop on Thrust Augmenting Ejectors
Author: Theoretical and Experimental Investigation of the Effect of Tunnel Walls on the Forces on an Oscillating Airfoil in Two-dimensional Subsonic Compressible Flow
Author: A. E. PotterPublisher:
ISBN:
Category : Aerodynamic load
Languages : en
Pages : 358
Book Description
An Experimental Investigation of Flow Surrounding an Airfoil with a Jet Exhausting from the Lower Surface
Author: Anjaneyulu KrothapalliPublisher:
ISBN:
Category : Aerodynamics
Languages : en
Pages : 118
Book Description
An Experimental Investigation of Flow Over an Oscillating Airfoil
Author: Panayiote GerontakosPublisher:
ISBN:
Category :
Languages : en
Pages : 218
Book Description
"The detailed behaviour of the unsteady boundary layer and stall events occurred on a sinusoidally oscillating NACA 0012 airfoil at Re = 1.35 x 105 was investigated experimentally by using closely-spaced multiple hot-film sensor arrays. The hot-film measurements were supplemented by surface pressure measurements, hot-wire wake velocity surveys and smoke-flow visualizations. Three typical oscillation parameters: attached flow, light stall, and deep stall were tested. Special attention was focused on the non-intrusive identification of the spatial-temporal progression of the locations of the boundary-layer transition and separation and reattachment points for a range of oscillation frequencies and amplitudes both prior to, during, and post the stall. The results show that for an unsteady airfoil, the reduced frequency of the oscillation was found to be highly significant and only small values of reduced frequency were required to delay the onset of the various boundary-layer events, and to produce significant variations and hysteresis in the peak values of lift and drag forces and the pitching moments, which are fundamentally different from their static counterparts. Lift stall was observed to occur when the leading-edge vortex reached 90% of the chord, while moment stall occurred at the end of the upward spread of the trailing-edge flow reversal. The convection speed of the leading-edge and the secondary vortices were also reported. Dynamic stall was found to be caused by an abrupt turbulent separation near the leading-edge region and not with the bursting of the laminar separation bubble, as is commonly observed for a static NACA 0012 airfoil; the result being the initiation, growth and convection of an energetic leading-edge vortex. Moreover, the detection of the sudden turbulent breakdown could serve as an indicator for dynamic stall detection and control. The results reported on here provide a deepened insight into the detailed nature of" --
Scientific and Technical Aerospace Reports
Author: Experimental Aerodynamic Derivatives of a Sinusoidally Oscillating Aerofoil with Jet Flap in Two-dimensional Incompressible Flow
Author: John M. SimmonsPublisher:
ISBN: 9780909683085
Category : Aerofoils
Languages : en
Pages : 170
Book Description
A Computational and Experimental Investigation of Incompressible Oscillatory Airfoil Flow and Flutter Problems
Author: Peter J. RiesterJournal of the American Helicopter Society
Author: American Helicopter SocietyPublisher:
ISBN:
Category : Helicopters
Languages : en
Pages : 690
Book Description