MechE Colloquium: Can we tailor the behavior of flexible sheets in flows by adding cuts or folds?


Event details

Date 25.04.2023
Hour 12:0013:00
Speaker Prof. Sophie Ramananarivo, Laboratoire d’hydrodynamique (LadHyX), Department of Mechanics, École Polytechnique Paris
Location Online
Category Conferences - Seminars
Event Language English
Abstract: Lightweight compliant surfaces are commonly used as roofs (awnings), filtration systems or propulsive appendages, that operate in a fluid environment. Their flexibility allows for shape to change in fluid flows, to better endure harsh or fluctuating conditions, or enhance flight performance of insect wings for example. The way the structure deforms is however key to fulfill its function, prompting the need for control levers. In this talk, we will consider two ways to tailor the deformation of surfaces in a flow, making use of the properties of origami (folded sheet) and kirigami (sheet with a network of cuts). Previous literature showed that the substructure of folds or cuts allows for sophisticated shape morphing, and produces tunable mechanical properties. We will discuss how those original features impact the way the structure interacts with a flow, through combined experiments and theory. We will notably show that a sheet with a symmetric cutting pattern can produce an asymmetric deformation, and study the underlying fluid-structure couplings to further program shape morphing through the cuts arrangement. We will also show that extreme shape reconfiguration through origami folding can cap fluid drag.

Biography: Sophie Ramananarivo is an Assistant Professor in the Department of Mechanics at École Polytechnique, and a researcher at LadHyX. After receiving her PhD in fluid-structure interaction at ESPCI-Paris in 2014, she continued her research as a postdoctoral fellow at the AML laboratory at the Courant Institute of NYU (New York), and then in the Department of Physics at UC San Diego. In 2017, she joined École Polytechnique as an Assistant Professor. Her research focuses on the interactions between fluids and solid objects that can move or deform. Her past work addressed questions relative to animal flight and swimming, such as the role of flows in formation of fish schools and bird flocks. She also investigated different forms of coupling at the microscopic scale, studying the interactions between microscopic swimmers and their colloidal environment. Currently, she is examining the interaction of highly flexible structures with fluid flow and exploring ways to control their response through their design.

Practical information

  • General public
  • Free



MechE Colloquium: Can we tailor the behavior of flexible sheets in flows by adding cuts or folds?