Frequency Response of Aerodynamic Load Control through Mini-tabs

Daniel Heathcote, Ismet Gursul, David Cleaver

Research output: Chapter in Book/Report/Conference proceedingConference contribution

2 Citations (Scopus)
80 Downloads (Pure)

Abstract

Load control is the reduction of extreme aerodynamic forces to enable lighter, more efficient aircraft. Current load control technologies are limited to low frequency disturbances. In this paper the mini-tab, a small, span-wise tab placed on the airfoil upper surface, is investigated as a high frequency alternative through periodic oscillations to identify its unsteady aerodynamic transfer function. Force measurements were conducted on a NACA0012 airfoil at a Reynolds number of 6.6x105 with a deployable mini-tab located at xf/c = 0.85, with actuation performed at reduced frequencies, k ≤ 0.79. The force measurements indicate that the mini-tab has a decreasing effect on lift reduction with increasing actuation frequency. This trend is comparable to Theodorsen’s function, based on the change in circulation. For α = 0°, the normalized peak-to-peak lift reduction decreased from 1 for steady state deployment to around 0.6 at k = 0.79. In addition, a phase lag exists between the mini-tab deployment and the aerodynamic response which increased with actuation reduced frequency, k. However, the measured phase lag is substantially larger than Theodorsen’s prediction. Increasing the angle of attack, α reduced the mini-tab’s effect on lift while increasing the phase angle when comparing equal k values. Particle Image Velocimetry measurements indicate that the delay and reduction in effectiveness of periodic deployment is due to the presence and growth of the separated region behind the mini-tab. Overall, the mini-tab was found to be an effective, dynamic lift reduction device with the separated region behind the mini-tab key to the amplitude and phase delay of lift response.
Original languageEnglish
Title of host publication55th AIAA Aerospace Sciences Meeting, 2017
PublisherAmerican Institute of Aeronautics and Astronautics
ISBN (Print)9781624104473
DOIs
Publication statusPublished - 11 Jan 2017
Event55th AIAA Aerospace Sciences Meeting: AiAA SciTech 2017 - Gaylord Texan, Grapevine, Texas, USA United States
Duration: 9 Jan 201713 Jan 2017

Conference

Conference55th AIAA Aerospace Sciences Meeting
CountryUSA United States
CityGrapevine, Texas
Period9/01/1713/01/17

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Aerodynamic loads
Frequency response
Aerodynamics
Force measurement
Airfoils
Angle of attack
Velocity measurement
Transfer functions
Reynolds number
Aircraft

Cite this

Heathcote, D., Gursul, I., & Cleaver, D. (2017). Frequency Response of Aerodynamic Load Control through Mini-tabs. In 55th AIAA Aerospace Sciences Meeting, 2017 [AIAA 2017-0947] American Institute of Aeronautics and Astronautics. https://doi.org/10.2514/6.2017-0947

Frequency Response of Aerodynamic Load Control through Mini-tabs. / Heathcote, Daniel; Gursul, Ismet; Cleaver, David.

55th AIAA Aerospace Sciences Meeting, 2017. American Institute of Aeronautics and Astronautics, 2017. AIAA 2017-0947.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Heathcote, D, Gursul, I & Cleaver, D 2017, Frequency Response of Aerodynamic Load Control through Mini-tabs. in 55th AIAA Aerospace Sciences Meeting, 2017., AIAA 2017-0947, American Institute of Aeronautics and Astronautics, 55th AIAA Aerospace Sciences Meeting, Grapevine, Texas, USA United States, 9/01/17. https://doi.org/10.2514/6.2017-0947
Heathcote D, Gursul I, Cleaver D. Frequency Response of Aerodynamic Load Control through Mini-tabs. In 55th AIAA Aerospace Sciences Meeting, 2017. American Institute of Aeronautics and Astronautics. 2017. AIAA 2017-0947 https://doi.org/10.2514/6.2017-0947
Heathcote, Daniel ; Gursul, Ismet ; Cleaver, David. / Frequency Response of Aerodynamic Load Control through Mini-tabs. 55th AIAA Aerospace Sciences Meeting, 2017. American Institute of Aeronautics and Astronautics, 2017.
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