Stokesian dynamics of periodically sheared active fluids

Active fluids are liquids containing a large number of “microswimmers” able to convert chemical energy into mechanical work.

Such energy conversion can be biological, as in the case of motile bacteria in the fluid interiors of animals; or it can be engineered, e.g microrobots or self-phoretic colloids designed for targeted drug delivery.

Despite such difference, active fluids share many fascinating signatures, e.g. collective motions and enhanced diffusion, due to the underlying hydrodynamic interactions (HIs). The present understanding of HIs, however, is only qualitative.

This project aims to provide quantitative insights into the role of HIs by performing rigorous, large-scale simulations of model active fluids.

Specifically, I will first implement various swimming models in a state-of-the-art numerical program to leverage its efficient and accurate computation of HIs.

Then, I will systematically simulate model active fluids in canonical and unexplored conditions to characterize the emerging properties.

These steps will be taken at the University of British Columbia (first two years, theory and simulation) and KTH Royal Institute of Technology (final year, result analyses). Broadly, active fluids are increasingly recognized as key to many vital industries, e.g. biomedicine and biofuels.

By developing a general computational tool, the crucial hydrodynamic effects in active fluids can be quantified and novel control strategies to direct their motions may be devised.