Repository logo

Infoscience

  • English
  • French
Log In
Logo EPFL, École polytechnique fédérale de Lausanne

Infoscience

  • English
  • French
Log In
  1. Home
  2. Academic and Research Output
  3. Journal articles
  4. Deformation of porous flexible strip in low and moderate Reynolds number flows
 
research article

Deformation of porous flexible strip in low and moderate Reynolds number flows

Pezzulla, M.
•
Strong, E. F.
•
Gallaire, F.  
Show more
August 21, 2020
Physical Review Fluids

We present results from a combined experimental and numerical investigation of the fluid-structure interaction of cantilevered porous flexible strips, towed through a fluid bath. We characterize the steady-state deformation of the strips and their associated drag, focusing on the low and moderate Reynolds (Re) number regimes. Our microfabricated strips offer independent control over porosity and permeability, a feature not available in previous studies. We fabricate strips with different levels of permeability, spanning over two orders of magnitude, while fixing their porosity at 50%. Then, the vertically clamped porous strips are towed inside a viscous bath. In parallel to the experiments, we model the strip as an elastica that is loaded locally by low (or moderate) Reynolds forces, via local drag coefficients. At low Re, we find that the drag coefficient, which can be obtained from Stokes simulations of rigid strips under perpendicular flow, varies with permeability by less than 10%. By contrast, at moderate Re, the drag coefficient depends significantly and nonmonotonically on permeability. Whereas porosity dictates the drag coefficient at low Re, our results demonstrate that a precisely designed permeability plays a major role at moderate Re, enabling large variations of the drag coefficients at a set level of porosity. Since porosity is directly linked to weight via the density of the effective solid, understanding how porous structures of fixed porosity and varying permeability interact with the surrounding fluid is of relevance to flying insects and microdrones.

  • Details
  • Metrics
Type
research article
DOI
10.1103/PhysRevFluids.5.084103
Web of Science ID

WOS:000561725700001

Author(s)
Pezzulla, M.
Strong, E. F.
Gallaire, F.  
Reis, P. M.
Date Issued

2020-08-21

Publisher

AMER PHYSICAL SOC

Published in
Physical Review Fluids
Volume

5

Issue

8

Article Number

084103

Subjects

Physics, Fluids & Plasmas

•

Physics

•

drag reduction

•

plates

•

wind

Editorial or Peer reviewed

REVIEWED

Written at

EPFL

EPFL units
LFMI  
FLEXLAB  
Available on Infoscience
September 5, 2020
Use this identifier to reference this record
https://infoscience.epfl.ch/handle/20.500.14299/171415
Logo EPFL, École polytechnique fédérale de Lausanne
  • Contact
  • infoscience@epfl.ch

  • Follow us on Facebook
  • Follow us on Instagram
  • Follow us on LinkedIn
  • Follow us on X
  • Follow us on Youtube
AccessibilityLegal noticePrivacy policyCookie settingsEnd User AgreementGet helpFeedback

Infoscience is a service managed and provided by the Library and IT Services of EPFL. © EPFL, tous droits réservés