Ricerc@Sapienza

The interaction of fluids and electric fields is at the heart of natural phenomena such as the disintegration of raindrops in thunderstorms and many practical applications such as electrosprays, inkjet printing, lab-on-a-chip and microfluidics. Yet, despite the method is widely used in several applications, fundamental knowledge of the mechanisms of emulsion demixing by electric fields and, in particular, the influence of surface active agents on drops placed in electric fields, is limited. The surface active agents (surfactants) are compounds that lower the surface tension between liquids, they are often used in pharmaceutical and engineering applications but also naturally present in heavy oils, e.g., asphaltenes, resins, etc; consequently it is of crucial importance to develop an improved understanding of the complex physics involved. Nowadays, numerical methods can offer a powerful tool to study very accurately such physical systems. Nevertheless, modelling these micro-fluidic processes is a challenging task, especially in three dimensions, because of the complex multiscale physics involved: large surface to volume ratio, many-body interaction, moving geometries and transport of surface active agents and of surface charges.
I propose to develop novel numerical methods for accurate micro-fluidic simulations of 3D drops in Stokes flow; this computational tool will be based on a boundary integral formulation, will consider the particles in both free space and confined geometries and it will include the effects of surfactants and electric fields.
To validate the simulations as well as to guide the modeling efforts, I will collaborate with Prof. Vlahovska (Northwestern University), who will run experiments in her Applied Math Lab.
With the integration of mathematical modeling, computations, and experiments we anticipate both a much deeper understanding of the underlying physics as well as the discovery of new dynamical regimes and engineering opportunities.