A piv study of baseline and controlled flow over a highly deflected flap of a generic trapezoidal wing

Konstantin Genschow, Philipp Tewes, Jesse C Little, Israel J Wygnanski

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

Abstract

The present study was conducted to improve the understanding of flow physics behind the highly deflected flap of a low aspect ratio, highly tapered, trapezoidal wing for baseline and actively controlled conditions. A semi-span model, based on a NACA0012 profile, was equipped with a flap hinged parallel to the trailing edge. Fluidic oscillators were installed at the trailing edge of the main element, just upstream of the flap shoulder, to increase the lift while maintaining longitudinal stability for high-lift conditions (i.e., large flap deflections). The Reynolds number in all experiments based on the root chord was 1,700,000. The flow over the flap, deflected at 55°, was analyzed for model incidences of 0° and 8° respectively using particle image velocimetry. Various planes parallel to the flap surface were measured in order to create a volumetric flow field. The baseline and controlled cases were analyzed and compared to surface flow visualization data, including tuft images and pressure sensitive paint. A strong flap leading edge vortex was detected at 0° incidence and active flow control limits the influence of this structure. Nevertheless, full attachment of the flow was not possible for this condition. For higher incidence (i.e., 8°), the actuators had a larger impact and attached the otherwise separated flow. This study shows that an array of fluidic oscillators is well suited to reattach massively separated flow over the flap of a low aspect ratio, highly tapered, trapezoidal wing. The control is less effective when the flow is partially attached due to the influence of the flap leading edge vortex.

Original languageEnglish (US)
Title of host publicationAIAA Aerospace Sciences Meeting
PublisherAmerican Institute of Aeronautics and Astronautics Inc, AIAA
Edition210059
ISBN (Print)9781624105241
DOIs
StatePublished - Jan 1 2018
EventAIAA Aerospace Sciences Meeting, 2018 - Kissimmee, United States
Duration: Jan 8 2018Jan 12 2018

Other

OtherAIAA Aerospace Sciences Meeting, 2018
CountryUnited States
CityKissimmee
Period1/8/181/12/18

Fingerprint

Fluidics
Aspect ratio
Vortex flow
Flow visualization
Flow control
Paint
Velocity measurement
Flow fields
Reynolds number
Actuators
Physics
Experiments

ASJC Scopus subject areas

  • Aerospace Engineering

Cite this

Genschow, K., Tewes, P., Little, J. C., & Wygnanski, I. J. (2018). A piv study of baseline and controlled flow over a highly deflected flap of a generic trapezoidal wing. In AIAA Aerospace Sciences Meeting (210059 ed.). American Institute of Aeronautics and Astronautics Inc, AIAA. https://doi.org/10.2514/6.2018-1801

A piv study of baseline and controlled flow over a highly deflected flap of a generic trapezoidal wing. / Genschow, Konstantin; Tewes, Philipp; Little, Jesse C; Wygnanski, Israel J.

AIAA Aerospace Sciences Meeting. 210059. ed. American Institute of Aeronautics and Astronautics Inc, AIAA, 2018.

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

Genschow, K, Tewes, P, Little, JC & Wygnanski, IJ 2018, A piv study of baseline and controlled flow over a highly deflected flap of a generic trapezoidal wing. in AIAA Aerospace Sciences Meeting. 210059 edn, American Institute of Aeronautics and Astronautics Inc, AIAA, AIAA Aerospace Sciences Meeting, 2018, Kissimmee, United States, 1/8/18. https://doi.org/10.2514/6.2018-1801
Genschow K, Tewes P, Little JC, Wygnanski IJ. A piv study of baseline and controlled flow over a highly deflected flap of a generic trapezoidal wing. In AIAA Aerospace Sciences Meeting. 210059 ed. American Institute of Aeronautics and Astronautics Inc, AIAA. 2018 https://doi.org/10.2514/6.2018-1801
Genschow, Konstantin ; Tewes, Philipp ; Little, Jesse C ; Wygnanski, Israel J. / A piv study of baseline and controlled flow over a highly deflected flap of a generic trapezoidal wing. AIAA Aerospace Sciences Meeting. 210059. ed. American Institute of Aeronautics and Astronautics Inc, AIAA, 2018.
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