Numerical Simulation on Impact of a Liquid Droplet on a Deep Liquid Pool for Low Impact Velocities

Droplet impact finds application in paint industries, spray coating, and aeration and hence becomes problem of engineering value. Velocity of impact, geometry, as well as the medium through which the droplet travels before it impacts the liquid surface plays a key role for the occurrence of droplet coalescence and droplet bouncing. In the present work attention has been given to low impact velocities ranging from 0.2 to 0.6 m/s for a droplet of diameter of 3 mm. Transition from coalescence to bouncing is observed at a velocity of 2 m/s. During the bouncing a secondary droplet forms and detaches from the parent droplet before it coalesces. Volume of fluids (VOF) method has been used to carry out the numerical simulation. VOF model is used for two or more immiscible fluids by solving a single set of momentum equation and it tracks the volume fraction of all the phases throughout the flow domain. Interface calculation has been done using Geometric Reconstruction Scheme using a Commercial software package.