Related Experiment Video
Updated: May 27, 2026
04:35
Preparation of Free-Surface Hyperbolic Water Vortices
Published on: July 28, 2023
Gyroid porous inserts as a novel flow control to mitigate tip vortex cavitation
Thomas Berger1, Mohamed Farhat1
1Institute of Mechanical Engineering, École Polytechnique Fédérale de Lausanne, Avenue de Cour 33 Bis, 1007 Lausanne, Switzerland.
Experiments in Fluids
|May 26, 2026
Summary
Gyroid-based porous tips effectively mitigate tip vortices by diffusing vorticity, significantly reducing cavitation risk and noise without impacting hydrodynamic performance. This passive flow control offers a promising solution for various fluid dynamics applications.
Area of Science:
- Fluid Dynamics
- Aerospace Engineering
- Naval Architecture
Background:
- Tip vortices from lifting surfaces cause drag, noise, and cavitation.
- Existing porous tips have shown limited effectiveness in vortex diffusion.
Purpose of the Study:
- Introduce and evaluate gyroid-based porous tips for tip vortex mitigation.
- Investigate the mechanism of vorticity diffusion and its impact on vortex characteristics.
- Assess the effect on cavitation and overall hydrodynamic performance.
Main Methods:
- Fabricated and attached gyroid porous inserts to a NACA 16-020 hydrofoil tip.
- Conducted Laser Doppler Velocimetry (LDV) measurements to analyze flow fields.
- Performed flow visualization to confirm cavitation suppression.
Main Results:
- Gyroid inserts reduced peak tangential velocity and increased vortex core radius.
- Cavitation was completely suppressed across all tested conditions.
- Hydrodynamic performance (lift and drag) was unaffected for inserts up to 5% span.
Conclusions:
- Gyroid-based porous tips are effective passive flow control devices for tip vortex mitigation.
- This technology significantly reduces cavitation risk and noise, preserving operational efficiency.
- Gyroid inserts show promise for applications in marine propellers, hydrofoils, aircraft wings, and wind turbines.
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