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Updated: Jan 21, 2026
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Free-form Light Actuators — Fabrication and Control of Actuation in Microscopic Scale
Published on: May 25, 2016
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Effects of Sweeping Jet Actuator Parameters on Flow Separation Control
1NASA Langley Research Center, Hampton, VA 23681.
AIAA Journal. American Institute of Aeronautics and Astronautics
|August 10, 2019
Summary
Sweeping jet actuators effectively control flow separation on ramps. Optimal performance is achieved with wider jet spreading and closer placement, with size variations impacting efficiency.
Area of Science:
- Fluid Dynamics
- Aerodynamics
- Flow Control
Background:
- Flow separation on adverse pressure gradient ramps is a significant challenge in aerodynamics.
- Traditional flow control methods like vortex generators and steady blowing have limitations.
Purpose of the Study:
- To parametrically investigate sweeping jet actuators (fluidic oscillators) for flow separation control.
- To determine the influence of actuator parameters on performance.
- To compare sweeping jet actuators with other flow control techniques.
Main Methods:
- Experimental study with surface pressure and oilflow visualization.
- 2D Particle Image Velocimetry and hot-wire anemometry for flow field analysis.
- Systematic variation of actuator parameters: blowing coefficients, operation mode, angles, location, and size.
Main Results:
- Sweeping jet actuators outperform steady blowing and vortex-generating jets for ramp flow control.
- Wider jet spreading (110°) and closer streamwise placement (2.3 boundary layer thickness) enhance performance.
- Scaling down actuator size affects jet spreading and efficiency; smaller actuators (1.9 × 0.95 mm) reduce efficiency.
Conclusions:
- Sweeping jet actuators offer a promising solution for flow separation control.
- Actuator design parameters, particularly jet spreading and placement, are critical for optimal performance.
- Insights gained can guide the design and selection of sweeping jet actuators for aerodynamic applications.
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