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arXiv · 2504.02053

Experimental observation of flow instability control by metamaterial subsurfaces

Melanie Keogh·Jensen McTighe·Jason Dahl·Osama R. Bilal
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Abstract

Flow instabilities within a fluid flow can cause laminar-to-turbulent transition over surfaces. These instabilities can result from upstream, wake-generating disturbances, leading to increased drag and turbulence-induced energy losses. Flow control strategies can address these issues through active methods, requiring energy input, or passive systems, which operate without added input. Here, we present a passive approach to flow control using embedded phononic metamaterials to alter vortex instability development, without changing the outer-surface's texture, roughness or compliance. Experiments confirm that our subsurface can suppress vortex growth at target frequencies, demonstrating the potential for energy-efficient flow management with phononic subsurfaces.

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Melanie Keogh, Jensen McTighe, Jason Dahl, Osama R. Bilal. 2025-04-02. Experimental observation of flow instability control by metamaterial subsurfaces. https://arxiv.org/abs/2504.02053

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