Some Measurements on Dynamic Stall

Parker, A. G.; Bicknell, Joseph

doi:10.2514/3.60351

Cited by 10 publications

(1 citation statement)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Such an arrangement can generate vertical (or lateral) velocity components according to the amplitude of the vane motion and the frequency of their operation. 10 Alternative arrangements, including fixed aerofoils with oscillating flaps, 11,12 fixed aerofoils with oscillating jet flaps, 13 aerofoils with circulation control 14 and rotating slotted cylinders, 15 have also been studied. These setups have, however, concentrated on the response of large aircraft operating at high flight speeds in the upper atmosphere rather than flight within the lower part of the atmospheric boundary layer where conditions cannot be assumed to be comparable.…”

Section: Introductionmentioning

confidence: 99%

The characterisation of a gust generator for aerodynamic testing

Saddington

Finnis

Knowles

2014

Proceedings of the Institution of Mechanical Engineers, Part G:

View full text Add to dashboard Cite

An experimental investigation was conducted to characterise the gust environment generated by a cascade of sinusoidally oscillating vanes in the Cranfield University 1.52 m by 1.14 m low-speed, open-jet, closed-circuit wind tunnel operating at 7.5 ms À1 and 14.5 ms À1 . Measurements were made at four stream-wise and three vertical positions in the flow-field downstream of the vanes using a cross-wire anemometer. The oscillation angle of the vanes was set at AE8 and AE12 with frequencies of 0.5 Hz, 1.0 Hz and 2.0 Hz corresponding to a reduced frequency of between 0.01 and 0.07. The vertical components of velocity and turbulence intensity were shown to be consistent for the range of measurement points chosen. The peak vertical velocity component downstream of the vanes was shown to be proportional to the maximum vane angle of attack but largely independent of reduced frequency.

show abstract

Section: Introductionmentioning

confidence: 99%

The characterisation of a gust generator for aerodynamic testing

Saddington

Finnis

Knowles

2014

Proceedings of the Institution of Mechanical Engineers, Part G:

View full text Add to dashboard Cite

show abstract

Unsteady aerodynamics of a wing in a novel small-amplitude transverse gust generator

Fernandez¹,

Cleaver²,

Gursul³

2020

Exp Fluids

View full text Add to dashboard Cite

A novel small-amplitude high-frequency gust generator has been developed that works by oscillating a small fence on the wind tunnel wall. The gust generator produces approximately constant local angle of attack in the chordwise direction. Due to the challenges of measuring small and slightly non-uniform gust angles the gust generator was calibrated using direct lift measurements on a symmetric wing set at zero geometric angle of attack. Unsteady lift force measurements and the Theodorsen's theory were used for the dynamic calibration of the gust angle. At nonzero geometric angles of attack, if the wing’s effective angle of attack remains below the stall angle, unsteady lift closely follows the static lift curve with very small hysteresis. Beyond the stall angle, dynamic stall and larger lift hysteresis are observed. Interestingly, in this regime, if flow is separated and a separation bubble is maintained on the wing throughout the cycle then increasing frequency reduces lift hysteresis. The slope of the lift curve, averaged over the cycle, may be greater than that of attached flow. The gust response is more sensitive to maximum effective angle of attack than the reduced frequency or the reduced pitch rate. The normalized lift change is much larger for separated flows than for attached flows. Graphic abstract

show abstract

Measurements of aerofoil unsteady stall properties with acoustic flow control

Moss

1979

Journal of Sound and Vibration

View full text Add to dashboard Cite

Some Measurements on Dynamic Stall

Cited by 10 publications

References 11 publications

The characterisation of a gust generator for aerodynamic testing

The characterisation of a gust generator for aerodynamic testing

Unsteady aerodynamics of a wing in a novel small-amplitude transverse gust generator

Measurements of aerofoil unsteady stall properties with acoustic flow control

Contact Info

Product

Resources

About