2021: B.Engg. Chemical Engineering +, Minor degree in Physics, BITS Pilani Goa.
Batchelor's Thesis: Stresslets in the Context of Biogenic Ocean Mixing
I am working with Prof Rama Govindarajan on studying fluid-particle interactions at intermediate and low Reynolds numbers. Particles may be classified as passive particles that are driven by an external force (such as falling droplets), or as active particles that can generate an internal force for movement (such as small swimming critters). Broadly, our work aims at understanding the underlying theory of these interactions and their implications in various physical scenarios. We use both numerics and experiments to carry out our studies.
Some of the questions we have been trying to answer are:
-How does Oseen flow compare with Stokes flow? How do their Green's functions compare with each other? What analogies can we draw between the two, and to what extent? While Stokes flow is a very extensively studied topic, and much literature is available on it, Oseen flow is relatively new and expanding, which makes it an exciting topic to explore. Check out my arXiv preprint for some work on this topic (linked below).
-How do small micron-sized passive particles emerging from a spray interact with each other? Are their interactions the dominant force driving their physics? Particulate sprays are found in many scenarios including industrial settings, where the flow rate, uniformity and spread of the spray may be important parameters determining the desired end results.
-How do small swimming critters (active particles) swim in a flow regime where inertia is just beginning to show up? How does this differ from microswimmers in Stokes flow?
In my undergraduate years, I worked on a CFD project that was inspired from observing turritella seashells on the beach. A turritella seashell's geometry consists of a whorl spiralling around an axis, forming an elongated conical shape. The seashell is known to have a unique hydrodynamic behaviour among other shells. Deriving interest from this, we demonstrated the suitability of the spiral turritella geometry in a static mixer application. A static mixer is a device with no moving parts, but that consists of a geometry that is designed in such a way that the incoming fluid is mixed.
Preprints and Publications:
3. Pujari, A. R. (2021). A direct approach to solving the hydrodynamic oseenlet. arXiv preprint: 2111.02369
2. Pujari, A. R., Kumar, S., & Sow, P. K. (2021). A Nature-inspired Turritella-seashell-like Static Mixer for Inline
Mixing. (under review)
1. Roy, S, Barari, S, Singh, R, Pujari, A. R., & Magare, B. A method of increasing the Hunter Whiteness of white
cement. Indian Patent Application: 202021003382, filed January 2020.
Apart from Research:
In my free time I enjoy reading and creative writing. Although writing is my main medium of expression, I occasionally explore different mediums like photography—essentially anything that brings forth a sense of aesthetic. Check out my blog and Instagram for some of these works.