Born at EPFL · Patent pending
Gyroid turns a mathematical surface into a 3D-printed insert that suppresses flow-induced vibration and cavitation on blades, foils and propellers, with no measurable loss in hydrodynamic performance.
Blade tip filmed at 10 000 frames per second in the EPFL cavitation tunnel. The white thread is a cavitating tip vortex. With the gyroid tip, it is gone.
The problem
When water or air flows past a blade, it rolls up into vortices. These vortices hit the structure with periodic forces, and they are behind some of the most expensive problems in fluid machinery.
Load restrictions, frequent maintenance stops, repairs of eroded blades, and lost production while machines stand still.
Rounded trailing edges, winglets or air injection help only partially, and always trade away some performance or add operational complexity.
Sources: vibration, Berger & Farhat, Scientific Reports (2025), reference blade 1.2 → 269 mm/s RMS; cracks, “Engineering diagnostics for vortex-induced stay vanes cracks in a Francis turbine”; erosion, US Bureau of Reclamation; ocean noise, McDonald et al., J. Acoust. Soc. Am. (2006); downtime, “Hydro turbine profitability and cavitation erosion”, ASCE (1999).
Applications
Anything that moves through water or air sheds vortices. We start where the technology has been tested and the need is greatest: hydropower.
First market
Francis turbines, about 60% of the world’s installed hydro capacity, can suffer severe trailing-edge vibration. Kaplan turbines are limited by tip-vortex cavitation, and industrial pumps face both. As an add-on, the insert could be retrofitted to machines already in service.
What operators could gain
Propeller cavitation erodes blades and radiates underwater noise, a growing concern for the protection of marine life. Mitigating tip vortices addresses both at the source.
The foils, rudders and appendages of high-speed sailing boats face the same vortex-induced vibration and cavitation that limit performance at speed.
Exploratory
The same principle applies in air: wind turbine blades, drone rotors, ventilation systems and aircraft profiles, where vortices mean noise, vibration and drag.
Results
Validated on hydrofoils in the EPFL high-speed cavitation tunnel, at industrial Reynolds numbers (up to 2 × 106) and flow speeds up to 20 m/s.
RMS vibration velocity falls from 268 to 1.3 mm/s.
The resonance is gone: less fatigue, longer blade life.
The vortex-shedding peak vanishes from the wake spectrum.
Calmer running across the whole speed range.
Completely suppressed with the gyroid tip, in every tested condition.
No erosion and no cavitation noise from the tip vortex.
Peak tangential velocity in the tip vortex, at 12° incidence.
A gentler vortex, far from the cavitation threshold.
Core radius at 12° incidence. The minimum pressure coefficient rises from −1.4 to −0.1.
A wide safety margin against cavitation.
Within measurement uncertainty (tip inserts up to 5% of the span).
No measurable performance penalty.
See it
Slow-motion visualisation of the wake behind the trailing edge, filmed at 20 000 frames per second.
A regular vortex street: each vortex pushes on the blade.
No organised vortices: the wake stays calm.
Slow-motion visualisation at the blade tip, filmed at 10 000 frames per second.
The pressure in the vortex core drops so low that the water boils: a thread of vapour trails from the tip.
With the gyroid tip, the vortex is spread out and its core stays above the cavitation threshold.
No vapor: no noise, no erosion.
Sources: T. Berger & M. Farhat, Scientific Reports (Nature Portfolio) 15, 25777 (2025); Experiments in Fluids 67:69 (2026).
How it works
The gyroid is a triply periodic minimal surface, identified by the mathematician Alan Schoen in 1970. It divides space into two interwoven networks of curved channels: porous, tortuous, light and stiff.
We 3D-print it as an insert and place it where vortices are born, at the trailing edge or at the blade tip. Inside it, the flow follows winding paths that break vortices up before they can organise.
sin x cos y + sin y cos z + sin z cos x = 0
The printed insert on the trailing edge of a steel hydrofoil.
At the trailing edge:
The insert generates alternating streamwise and transverse jets that keep the wake stable far downstream. Alternate vortices can no longer roll up, so the periodic forcing and the lock-in disappear.
At the blade tip:
The insert spreads the concentrated vorticity over a much wider core while total circulation stays the same. Swirl velocity drops, so the pressure at the vortex centre stays far above the cavitation threshold.
Where we stand
Gyroid is a project in development. The effect was discovered in the tunnel first; the physics behind it is now being worked out in detail.
1889
“The tower’s porous structure is undoubtedly what saved it.”
Completed two decades before von Kármán explained vortex streets, the tower’s porosity gave Thomas Berger the idea behind the gyroid insert.
Origin
Early in his PhD, Thomas Berger 3D-prints a gyroid, glues it onto the trailing edge of a steel hydrofoil and tests it in the tunnel. Vortex shedding disappears.
2025
PCT application WO2025/099062A1, “Fluid engaging device with a vortex mitigating component”.
Jul 2025
Published in Scientific Reports (Nature Portfolio): 99.5% vibration reduction at lock-in, no change in lift or drag.
Sep 2025
EPFL News covers the invention.
2026
Published in Experiments in Fluids and featured in the hydropower dossier of Bulletin SEV/VSE.
Now
Turning the research into a company that can bring the technology to industry.
Next
Validation under the more complex flows found inside turbines, pumps and propellers.
Team
Inventor · PhD candidate in mechanical engineering, EPFL
Designed and experimentally validated the gyroid technology for passive vortex control, combining mathematics, 3D modelling and 3D printing.
Co-inventor · Senior scientist (MER), EPFL
Head of the cavitation research group at EPFL's School of Engineering, specialist in complex flows and cavitation in hydraulic turbomachinery.
Publications & press
Berger & Farhat · Scientific Reports 15, 25777 (2025)
Read the paper Peer-reviewedBerger & Farhat · Experiments in Fluids 67:69 (2026)
Read the paper PatentFarhat & Berger · PCT WO2025/099062A1
View on WIPO Patentscope PressEPFL News · 19 September 2025
Read the article PressBulletin SEV/VSE · 4/2026 · Hydropower dossier
Read the articleContact
Whether you run turbines, pumps or propellers, build them, or would like to support the project, we would be glad to hear from you.
thomas.berger@gyroid.chThomas Berger, inventor · Lausanne, Switzerland