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Updated: Mar 2, 2026
09:58
Investigating the Three-dimensional Flow Separation Induced by a Model Vocal Fold Polyp
Published on: February 3, 2014
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The flow separation delay in the boundary layer by induced vortices.
Ishtiaq A Chaudhry1,2, Tipu Sultan3, Farrukh A Siddiqui4
1School of Mechanical Aerospace and Civil Engineering, University of Manchester, Manchester, UK.
Journal of Visualization
|May 19, 2017
Summary
Synthesized streamwise vortices effectively control flow separation. Particle image velocimetry experiments demonstrate vortical structures delay boundary layer separation and promote reattachment.
Area of Science:
- Fluid Dynamics
- Aerodynamics
Background:
- Flow separation is a critical phenomenon in fluid dynamics, negatively impacting aerodynamic performance.
- Controlling flow separation is essential for enhancing efficiency in various engineering applications.
Purpose of the Study:
- To quantitatively assess the effectiveness of synthesized vortical structures for flow separation control.
- To investigate the impact of different synthetic jet actuator configurations on boundary layer behavior.
Main Methods:
- Particle image velocimetry (PIV) was employed to analyze flow dynamics.
- Streamwise vortices were synthesized using synthetic jet actuators.
- Experiments were conducted on a flat plate with attached and separating boundary layers.
Main Results:
- Single circular jets demonstrated the interaction dynamics between vortices and low-momentum fluid.
- Arrays of jets showed effectiveness in reattaching separated flows.
- Vortical structures were found to delay boundary layer separation.
Conclusions:
- Synthesized vortical structures offer a viable method for flow separation control.
- Actuator geometry and operating parameters significantly influence vortex evolution and control effectiveness.
- The study provides quantitative insights into vortex-flow interactions for aerodynamic applications.
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