Droplet coalescence and breakup: Numerical simulations using moving mesh interface tracking with dynamic mesh adaptation

TL;DR

This paper presents a numerical simulation method for droplet coalescence and breakup using a moving mesh interface tracking approach with adaptive mesh refinement, capable of capturing large deformations and thin regions.

Contribution

It introduces a finite volume/moving mesh interface tracking method with dynamic mesh adaptation for accurately simulating droplet dynamics.

Findings

Mesh adaptation captures large deformations and thin regions.

Smallest length scale resolved is three orders of magnitude smaller than droplet radius.

Simulations successfully demonstrate droplet breakup and coalescence phenomena.

Abstract

Droplet(s) breakup and coalescence have been simulated by the finite volume/moving mesh interface tracking method (MMIT) with adaptive mesh refining and coarsening. In this method, the interface is zero-thickness and moves in a Lagrangian fashion. The breakup and the coalescence of the interfaces are simulated by the mesh separation and mesh combination schemes. Three cases are displayed in this video, which include the relaxation and breakup of an initially extended droplet, two identical droplets off-center collision, and a droplet pair in a shear flow. The mesh adaptation is capable of capturing large deformations and thin regions, and the smallest length resolved is three orders of magnitude smaller than the droplet radius. The fluid dynamics videos of the simulations are to be presented in the Gallery of Fluid Motion, 2010.