Periodic forcing in viscous fingering of a nematic liquid crystal

R. Folch, T. Tóth-Katona, A. Buka, J. Casademunt, A. Hernández-Machado

Research output: Contribution to journalArticle

Abstract

Viscous fingering of an air-nematic interface in a radial Hele-Shaw cell is studied when periodically switching on and off an electric field, which reorients the nematic and thus changes its viscosity, as well as the surface tension and its anisotropy (mainly enforced by a single groove in the cell). Undulations at the sides of the fingers are observed that correlate with the switching frequency and with tip oscillations that give maximal velocity to smallest curvatures. These lateral undulations appear to be decoupled from spontaneous (noise induced) side branching. It is concluded that the lateral undulations are generated by successive relaxations between two limiting finger widths. The change between these two selected pattern scales is mainly due to the change in the anisotropy. This scenario is confirmed by numerical simulations in the channel geometry, using a phase-field model for anisotropic viscous fingering.

Original languageEnglish
Number of pages1
JournalPhysical Review E - Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics
Volume64
Issue number5
DOIs
Publication statusPublished - Jan 1 2001

Fingerprint

Periodic Forcing
Nematic Liquid Crystal
Anisotropy
Lateral
liquid crystals
Hele-Shaw
anisotropy
Phase Field Model
Cell
cells
Surface Tension
grooves
Correlate
Branching
Electric Field
Viscosity
interfacial tension
Limiting
Curvature
curvature

ASJC Scopus subject areas

  • Statistical and Nonlinear Physics
  • Statistics and Probability
  • Condensed Matter Physics

Cite this

Periodic forcing in viscous fingering of a nematic liquid crystal. / Folch, R.; Tóth-Katona, T.; Buka, A.; Casademunt, J.; Hernández-Machado, A.

In: Physical Review E - Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics, Vol. 64, No. 5, 01.01.2001.

Research output: Contribution to journalArticle

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