Mass Transfer Enhancement by a Single Emulsion Droplet

The mass transfer enhancement (MTE) by a single emulsion droplet subjected to a Poiseuille flow is studied by using h-adaptive finite element approximation. The Navier-Stokes equations with the surface tension force at a droplet-fluid phase for the fluid flows are considered. The mass transfer is modeled by convection-diffusion equation. The interface capturing method with a conservative level set approach is employed to track the interface of a droplet. This is also incorporated with a mesh adaptivity for increasing the resolution in vicinity of the interface of the droplet. We numerically investigate the effect of hydrodynamic interactions of the droplet with the fluid on the mass transfer in varying physical parameters of the fluid flows and the suspended droplet in order to find the optimum conditions to invoke the enhanced MTE. It is found that Pe is an important factor to enhance the mass transfer transported by the convective current with diffusion. It is also found that Ca is an important factor for MTE considering disturbances and deformability of the droplet during the mass transfer process. It is found that the MTE decreases with increasing Ca in a high concentration region (C=0.9) while MTE does not depend much on Ca in a low concentration region (C=0.1).