Numerical Simulation of Leaky Dielectric Droplet in Couette Flow under Electric Field

In this study, the deformation and heat transfer of a leaky dielectric droplet in Couette flow under electric stresses is simulated. The level-set method along with the ghost fluid method is adopted to model the interface in a sharp manner. The simulation results are compared with available numerical and analytical data and a satisfactory agreement is observed. In the absence of electric field the effect of Reynolds and capillary numbers is considered. The droplet deformation increases with both Reynolds number and capillary number. However, the effect of the Reynolds number is slight. Under combined effect of shear flow and electric field, the droplet starts to deform and finally reaches the equilibrium. The droplet deformation enhances with electric capillary number. At higher electric field strengths, this enhancement occurs at a higher rate. The time required for the droplet to reach the equilibrium shape increases with electric field strength. It was observed that the electric field increases the heat transfer rate in this phenomenon. At higher electric field strength, the droplet reaches the thermal equilibrium faster.

Keywords:

Leaky dielectric , Droplet , Couette flow , Electric field