Fluid front morphologies in gap-modulated Hele-Shaw cells

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

  • Lautaro Díaz-Piola - , University of Barcelona (Author)
  • Ramon Planet - , University of Barcelona (Author)
  • Otger Campàs - , University of California at Santa Barbara (Author)
  • Jaume Casademunt - , University of Barcelona (Author)
  • Jordi Ortín - , University of Barcelona (Author)

Abstract

We consider the displacement of an inviscid fluid (air) by a viscous fluid (oil) in a narrow channel with gap-thickness modulations. The interfacial dynamics of this problem is strongly nonlocal and exhibits competing effects from capillarity and permeability. We derive analytical predictions of steady-state front morphologies, which are exact at linear level in the case of a persistent modulation in the direction of front advancement. The theoretical predictions are in good agreement with experimental measurements of steady-state front morphologies obtained in a Hele-Shaw cell with modulations of the channel depth, consisting on three parallel tracks of reduced depth, for small gap modulations. The relative average distance between theoretical and experimental fronts in the region around the central track is smaller than about 4%, provided that the height of the tracks is less than 13% of the total channel depth and the local distortion of the front height h is small enough (|h|<0.8) for the linear approximation to hold.

Details

Original languageEnglish
Article number094006
JournalPhysical review fluids
Volume2
Issue number9
Publication statusPublished - Sept 2017
Peer-reviewedYes
Externally publishedYes