Title of the talk: "Stability Analysis of Thermoconvective Flows with Applications to CO₂ Sequestration"

Date , Time & Venue: 25 August 2025  at 12 PM on Seminar Hall, Dept. of Mathematics

Abstract: Stability analysis of thermoconvective flows plays a crucial role in understanding various geophysical and industrial phenomena, including oceanography, mantle convection, and nuclear reactors. In this talk, I will present two approaches for analyzing the stability of such systems: linear theory and the energy method. I then discuss how the convective instability analysis is relevant to carbon sequestration, a promising strategy for reducing greenhouse gas emissions by storing CO₂ in deep underground aquifers. The long-term behavior of this process depends critically on the mixing of CO₂ with resident brine, which is strongly influenced by buoyancy-driven convection resulting from concentration differences and geothermal temperature gradients. To analyze this, we study the stability of thermosolutal convection arising from vertical temperature and concentration gradients and determine the critical Rayleigh number for the onset of instability. Notably, the linear theory and energy method yield the same stability threshold, indicating that the subcritical instability region is negligible. This highlights a unique instability characteristic of the system and underscores its relevance for predicting and enhancing mixing in underground aquifers. Finally, I illustrate the applicability of these results to CO₂ sequestration scenarios.

About the Speaker: Dr. Kapil Dev’s academic journey began with a Bachelor’s degree in Physics, Chemistry, and Mathematics from the University of Rajasthan (Jaipur) in 2015, after which he completed M.Sc. in Mathematics at the same university in 2018.  In August 2019, Dr. Kapil joined the Ph.D. in Mathematics at MNIT Jaipur under the supervision of Dr. Om P. Suthar. By December 29, 2023, He had successfully defended my thesis, titled “Study of the Stability of Thermoconvective Flows using the Energy Method.” During his doctoral research, his investigations delved into the stability of thermoconvective flows under various configurations, including double diffusion, ferrofluids, surface tension effects, non-uniform heating, and side-wall effects, leading to publications in international journals. Since April 2024, He work as an Institute Post-Doctoral Fellow in the Department of Civil Engineering, IIT Kanpur, has focused on the application of thermoconvective stability in CO₂ sequestration and the study of gravity-driven flows using both numerical and experimental tools.