Effect of Sweep on Dynamic Stall of a Pitching Finite-Aspect-Ratio Wing

Miguel R. Visbal; Daniel J. Garmann

doi:10.2514/1.j058206

Control of Dynamic Stall Over a Pitching Finite-Aspect-Ratio Wing

47th AIAA Fluid Dynamics Conference ◽

10.2514/6.2017-4118 ◽

2017 ◽

Cited By ~ 3

Author(s):

Miguel R. Visbal ◽

Daniel J. Garmann

Keyword(s):

Aspect Ratio ◽

Dynamic Stall

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Experimental Performance of a Trochoidal Propeller with High-Aspect-Ratio Blades

Marine Technology and SNAME News ◽

10.5957/mt1.1989.26.3.192 ◽

1989 ◽

Vol 26 (03) ◽

pp. 192-201 ◽

Cited By ~ 1

Author(s):

Neil Bose ◽

Peter S. K. Lai

Keyword(s):

Aspect Ratio ◽

High Efficiency ◽

Open Water ◽

Finite Amplitude ◽

Dynamic Stall ◽

Frictional Drag ◽

Overall Performance ◽

Small Ship ◽

Propeller Performance ◽

Thrust And Torque

Open-water experiments were done on a model of a cycloidal-type propeller with a trochoidal blade motion. This propeller had three blades with an aspect ratio of 10. These experiments included the measurement of thrust and torque of the propeller over a range of advance ratios. Tests were done for forward and reverse operation, and at zero speed (the bollard pull condition). Results from these tests are presented and compared with: a multiple stream-tube theoretical prediction of the performance of the propeller; and a prediction of the performance of a single blade of the propeller, oscillating in heave and pitch, using unsteady small-amplitude hydrofoil theory with corrections for finite amplitude motion, finite span, and frictional drag. At present, neither of these theories gives a completely accurate prediction of propeller performance over the whole range of advance ratios, but a combination of these approaches, with an allowance for dynamic stall of the blades, should lead to a reliable simple theory for overall performance prediction. Application of a propeller of this type to a small ship is discussed. The aim of the design is to produce a lightly loaded propeller with a high efficiency of propulsion.

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Effect of Aspect Ratio on Swept Wing Dynamic Stall

AIAA AVIATION 2021 FORUM ◽

10.2514/6.2021-2948 ◽

2021 ◽

Author(s):

Patrick R. Hammer ◽

Daniel J. Garmann ◽

Miguel R. Visbal

Keyword(s):

Aspect Ratio ◽

Dynamic Stall ◽

Swept Wing

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Dynamic Stall of a Finite-Aspect-Ratio Wing

AIAA Journal ◽

10.2514/1.j057457 ◽

2019 ◽

Vol 57 (3) ◽

pp. 962-977 ◽

Cited By ~ 11

Author(s):

Miguel R. Visbal ◽

Daniel J. Garmann

Keyword(s):

Aspect Ratio ◽

Dynamic Stall

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Influence of Aspect Ratio on Dynamic Stall of a Finite Wing

2018 AIAA Aerospace Sciences Meeting ◽

10.2514/6.2018-0546 ◽

2018 ◽

Cited By ~ 2

Author(s):

Ignacio Andreu Angulo ◽

Phillip J. Ansell

Keyword(s):

Aspect Ratio ◽

Dynamic Stall ◽

Finite Wing

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Dynamic Stall Characteristics of Pitching Swept Finite-Aspect-Ratio Wings

Fluids ◽

10.3390/fluids6120457 ◽

2021 ◽

Vol 6 (12) ◽

pp. 457

Author(s):

Al Habib Ullah ◽

Kristopher L. Tomek ◽

Charles Fabijanic ◽

Jordi Estevadeordal

Keyword(s):

Aspect Ratio ◽

Separation Bubble ◽

Leading Edge ◽

Dynamic Stall ◽

Trailing Edge ◽

Sweep Angle ◽

Pitching Motion ◽

Naca0012 Airfoil ◽

Phase Average ◽

Reduced Frequency

An experimental investigation regarding the dynamic stall of various swept wing models with pitching motion was performed to analyze the effect of sweep on the dynamic stall. The experiments were performed on a wing with a NACA0012 airfoil section with an aspect ratio of AR = 4. The experimental study was conducted for chord-based Reynolds number Rec =2×105 and freestream Mach number Ma=0.1. First, a ‘particle image velocimetry’ (PIV) experiment was performed on the wing with three sweep angles, Λ=0o, 15o, and 30o, to obtain the flow structure at several wing spans. The results obtained at a reduced frequency showed that a laminar separation bubble forms at the leading edge of the wing during upward motion. As the upward pitching motion continues, a separation burst occurs and shifts towards the wing trailing edge. As the wing starts to pitch downward, the growing dynamic stall vortex (DSV) vortex sheds from the wing’s trailing edge. With the increasing sweep angle of the wing, the stall angle is delayed during the dynamic motion of the wing, and the presence of DSV shifts toward the wingtip. During the second stage, a ‘turbo pressure-sensitive paint’ (PSP) technique was deployed to obtain the phase average of the surface pressure patterns of the DSV at a reduced frequency, k=0.1. The phase average of pressure shows a distinct pressure map for two sweep angles, Λ=0o, 30o, and demonstrates a similar trend to that presented in the published computational studies and the experimental data obtained from the current PIV campaign.

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