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arXiv · 2309.04136

Shape-Morphing Dynamics of Soft Compliant Membranes for Drag and Turbulence Modulation

Varghese Mathai·Asimanshu Das·Dante L. Naylor·Kenneth S. Breuer
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Abstract

We study the kinematics and dynamics of a highly compliant membrane disk placed head-on in a uniform flow. With increasing flow velocity, the membrane deforms nonlinearly into increasingly parachute-like shapes. These aerodynamically elongated materials exhibit a modified drag law, which is linked to the elastohydrodynamic interactions. We predict the unsteady structural response of the membranes using a nonlinear, aeroelastic model -- in excellent agreement with experimental measurements of deformations and force fluctuations. With simultaneous membrane interface tracking, force measurements and flow tracing, we reveal that a peculiar skewness in the membrane's oscillations triggers turbulence production in the wake, thereby modulating the drag. The present work provides a demonstration of the complex interplay between soft materials and fluid turbulence, leading to new, emergent system properties.

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Varghese Mathai, Asimanshu Das, Dante L. Naylor, Kenneth S. Breuer. 2023-09-08. Shape-Morphing Dynamics of Soft Compliant Membranes for Drag and Turbulence Modulation. https://arxiv.org/abs/2309.04136

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