Research
My research interests lie in phenomena involving fluid mechanics that can be explained with the application of techniques borrowed from applied mathematics and computational methods. Most of my research work is motivated by experiments on complex and biological fluids and can be broadly divided into two categories.
Simple substances can be classified into liquid or crystalline solids. On the other hand, some condensed-phase materials are neither simple liquids nor crystalline solids. These "complex fluids" possess mechanical properties that are intermediate between liquids and solids. A non-exhaustive list of complex fluids include viscoelastic fluids, glass-forming liquids, polymers, micellar solutions, magnetorheological and electrorheological fluids. My research work has focused on the latter. The dynamics of dielectric rigid particles and liquid drops suspended in another liquid medium and subject to a uniform DC electric field, the study of which forms the field of electrohydrodynamics (EHD), has fascinated scientists for decades. This phenomenon is described by the much celebrated Melcher-Taylor leaky dielectric model. While there have been numerous studies on the dynamics of particles and drops more conducting than the surrounding liquid medium, weakly conducting particles and drops in strong electric fields, known to undergo symmetry-breaking bifurcations leading to steady rotation known as Quincke electrorotation, have received much less attention. Using a combination of analytical and computational methods, we have been able to explain experiments on drops and particles under Quincke rotation and reproduce them in simulations.
In recent years, there has been a plethora of work that has underscored the importance of fluid mechanics in biological systems. The key to understanding some of these phenomena in biological systems has been to understand the fluid mechanics driving these phenomena. My postdoctoral research work is mainly concerned with swimming or locomotion of micro-organisms. Swimming at low-Reynolds numbers (micro-scale) can be quite challenging due to the Scallop's theorem. However, nature has found a way around it by enabling micro-organisms to create non-reciprocal motion. In this area of research, I am interested in modelling the dynamics of swimming micro-organisms like the beating motion of sperm-tails or rotating motion of bacterial flagella using resistive force, slender body theories and boundary element methods.
