Computing the viscous effect in early-time drop impact dynamics

Kavli Affiliate: Shmuel M. Rubinstein

| First 5 Authors: Shruti Mishra, Shmuel M. Rubinstein, Chris H. Rycroft, ,

| Summary:

The impact of a liquid drop on a solid surface involves many intertwined
physical effects, and is influenced by drop velocity, surface tension, ambient
pressure and liquid viscosity, among others. Experiments by Kolinski et al.
(2014b) show that the liquid-air interface begins to deviate away from the
solid surface even before contact. They found that the lift-off of the
interface starts at a critical time that scales with the square root of the
kinematic viscosity of the liquid. To understand this, we study the approach of
a liquid drop towards a solid surface in the presence of an intervening gas
layer. We take a numerical approach to solve the Navier-Stokes equations for
the liquid, coupled to the compressible lubrication equations for the gas, in
two dimensions. With this approach, we recover the experimentally captured
early time effect of liquid viscosity on the drop impact, but our results show
that lift-off time and liquid kinematic viscosity have a more complex
dependence than the square root scaling relationship. We also predict the
effect of interfacial tension at the liquid-gas interface on the drop impact,
showing that it mediates the lift-off behavior.

| Search Query: ArXiv Query: search_query=au:”Shmuel M. Rubinstein”&id_list=&start=0&max_results=10

Read More

Leave a Reply