A COMSOL Multiphysics® Model of Droplet Formation at a Flow Focusing Device

A. Abrishamkar[1], A.S. Rane[1], K.S. Elvira[1], R.C.R. Wootton[1], T. Sainio[2], A.J. deMello[1]
[1]Swiss Federal Institute of Technology (ETH), Zurich, Switzerland
[2]Lappeenranta University of Technology, Lappeenranta, Finland
Published in 2013

In this work, we numerically investigated the process of droplet generation using water as the dispersed phase and FC-40 oil as the continuous phase in a microfluidic device. We used a two-phase level set method in COMSOL Multiphysics® for our study. The simulations were carried out in a two dimensional domain through a flow-focusing droplet generator. The effect of the velocity ratio between the aqueous and oil phases on droplet size was studied using two sets of simulations. The results demonstrate that the velocity ratio of the two phases directly determine the size of the droplets. Both sets of simulations indicate similar droplet sizes for same ratio of input velocities.