Electrohydrodynamic instabilities in thin viscoelastic films - AC and DC fields

Leonardo Espín, Andrew Corbett, Satish Kumar

Research output: Contribution to journalArticle

21 Scopus citations

Abstract

Electrohydrodynamic instabilities in thin liquid films are a promising route for the self-assembly of well-defined topographical features on the surfaces of materials. Here, we study the effect of viscoelasticity on these instabilities under the influence of AC and DC electric fields. Viscoelasticity is incorporated via a Jeffreys model, and both perfect and leaky dielectric materials are considered. In the case of DC fields, asymptotic methods are employed to shed light on the nature of a singularity that arises when solvent viscosity is neglected (i.e., the Maxwell-fluid limit). In the case of AC fields, we apply a numerical procedure based on Floquet theory to determine the maximum growth rate and corresponding wave number as a function of the oscillation amplitude and frequency. Elasticity is found to increase both the maximum growth rate and corresponding wave number, with the effects being most pronounced when the oscillation period is comparable to the fluid relaxation time.

Original languageEnglish (US)
Pages (from-to)102-111
Number of pages10
JournalJournal of Non-Newtonian Fluid Mechanics
Volume196
DOIs
StatePublished - Jun 1 2013

Keywords

  • Electrohydrodynamics
  • Instability
  • Thin films
  • Viscoelasticity

Fingerprint Dive into the research topics of 'Electrohydrodynamic instabilities in thin viscoelastic films - AC and DC fields'. Together they form a unique fingerprint.

  • Cite this