(334f) Dynamics of Deformable Sheets in Stokes Flow

Fundamental dynamics of particles in flow are important to understand complicated real-world applications. Sheets with negligible thickness are commonly observed in microscale fluid-based thin film processing and some origami-inspired folding devices, but the related fundamental dynamics of such structures in fluid are poorly understood. We perform numerical simulations to study the dynamics of a thin sheet freely suspended in Stokes flow. The model accounts for two aspects of mechanical responses: in-plane deformation and out-of-plane bending. We study the dynamics in both shear and extensional flows. A deformable sheet can show complicated dynamics such as 2D tank-treading and involves interesting mechanical instabilities such as buckling and wrinkling that further lead to the self-folding of the sheet. The folding behavior is closely related to the deformability and initial position. We also examine a sheet near a solid boundary to understand the influence of deformability on the near-wall dynamics.