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Updated: Jun 3, 2026

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Published on: April 23, 2018
Control of vortex shedding on two- and three-dimensional aerofoils
Tim Colonius1, David R Williams
1Department of Mechanical Engineering, California Institute of Technology, Pasadena, CA 91125, USA. colonius@caltech.edu
This study explores controlling separated flows over airfoils for micro air vehicles. It unifies experimental data on lift response to actuation by examining vortex shedding for better flow control.
Area of Science:
- Fluid dynamics
- Aerodynamics
- Micro air vehicle technology
Background:
- Separated flows over airfoils at low Reynolds numbers are critical for micro air vehicle (MAV) performance.
- Understanding and controlling these flows is essential for improving MAV maneuverability and efficiency.
Purpose of the Study:
- To review and expand on control strategies for separated flows over flat plates and aerofoils at low Reynolds numbers.
- To unify experimental observations of lift response to actuation based on vortex shedding.
- To examine closed-loop flow and flight control using leading-edge vortex actuation.
Main Methods:
- Review of experimental observations on steady-state and transient lift response to actuation.
- Analysis of factors influencing lift response: actuator type, airfoil geometry, and flow conditions.
- Examination of strategies for closed-loop control via leading-edge vortex actuation.
Main Results:
- Lift response to actuation is linked to the excitation of periodic and transient vortex shedding.
- A unified understanding of lift response based on vortex dynamics is proposed.
- Strategies for closed-loop control using leading-edge vortex actuation are investigated.
Conclusions:
- Actuation strategies can effectively control separated flows over airfoils at low Reynolds numbers.
- Vortex shedding dynamics provide a framework for unifying and predicting lift response.
- Leading-edge vortex actuation shows promise for advanced closed-loop flow and flight control in MAVs.
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