2023/09/08 by Varghese Mathai, Mathai, Varghese, Asimanshu Das +5 · 1 citation
Engineering · Physics and Astronomy · #Advanced Materials and Mechanics #Biomimetic flight and propulsion mechanisms #FOS: Physical sciences #Fluid Dynamics (physics.flu-dyn) #Micro and Nano Robotics #Soft Condensed Matter (cond-mat.soft)
paper · pdf · doi:10.48550/arxiv.2309.04136
openalex publication_date 2023/09/08 · openalex created_date 2023/09/12 · openalex updated_date 2026/07/28
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.