Odd-viscosity-induced stabilization of viscous thin liquid films. (4th September 2019)

• Record Type: Journal Article
• Authors: Kirkinis, E.; Andreev, A. V.
• Is Part Of: Journal of fluid mechanics. Volume 878(2019)
• Page Start: 169
• Page End: 189
• Publication Date: 2019-09-04
• Subjects: thin films, -- capillary waves; Fluid mechanics -- Periodicals; 532.005
• DOI: 10.1017/jfm.2019.644
• Languages: English
• ISSNs: 0022-1120

Abstract

Abstract : Thin viscous liquid films sitting on a solid substrate support nonlinear capillary waves, driven by surface shear stresses at a liquid–gas interface. When surface tension is spatially dependent other mechanisms, such as the thermocapillary effect, influence the dynamics of thin films. In this article we show that in liquids with broken time-reversal symmetry the character of the aforementioned waves and of the thermocapillary effect are significantly modified due to the presence of odd or Hall viscosity in the liquid. This is because odd viscosity gives rise to new terms in the pressure gradient of the flow thus modifying the evolution equation of the liquid–gas interface accordingly. These terms in turn break the reflection symmetry of the evolution equation leading the system to evolve from a pitchfork to a Hopf bifurcation. The odd-viscosity incipient waves can stabilize unstable thin liquid films. For instance, we show that they can suppress the thermocapillary instability. We establish the parameter ranges that odd viscosity has to satisfy in order to initiate those waves that will lead to stability.