The role of inertia in the rupture of ultrathin liquid films Articles uri icon

publication date

  • November 2020

start page

  • 1

end page

  • 12

issue

  • 11

volume

  • 32

International Standard Serial Number (ISSN)

  • 1070-6631

Electronic International Standard Serial Number (EISSN)

  • 1089-7666

abstract

  • Theory and numerical simulations of the Navier&-Stokes equations are used to unravel the influence of inertia on the dewetting dynamics of an ultrathin film of Newtonian liquid deposited on a solid substrate. A classification of the self-similar film thinning regimes at finite Ohnesorge numbers is provided, unifying previous findings. We reveal that, for Ohnesorge numbers smaller than one, the structure of the rupture singularity close to the molecular scales is controlled by a balance between liquid inertia and van der Waals forces, leading to a self-similar asymptotic regime with hmin &;8733# tau2/5 as tau → 0, where hmin is the minimum film thickness and tau is the time remaining before rupture. The flow exhibits a three-region structure comprising an irrotational core delimited by a pair of boundary layers at the wall and at the free surface. A potential-flow description of the irrotational core is provided, which is matched with the vortical layers, allowing us to present a complete parameter-free asymptotic description of inertia-dominated film rupture.

keywords

  • disjoining pressure; laminar flows; liquid solid interfaces; thin films; van der waals forces; navier stokes equations; intermolecular forces; newtonian fluids