Computational Analysis of Rayleigh-Bénard Convection in an Enclosure: A Comparative Study of Nitrogen Gas and Carbon Dioxide
Discipline: Technology and Engineering
Subcategory: Civil/Mechanical/Manufacturing Engineering
Session: 4
Room: Eastern Market
Ivana Barley - Southern University and A&M College
Co-Author(s): Stephen Akwaboa, Southern University and A&M College, Baton Rouge, Louisiana; Patrick Mensah, Southern University and A&M College, Baton Rouge, Louisiana;
This research investigates Rayleigh-Bénard convection within an enclosure, focusing on two distinct gases, nitrogen (N2) and carbon dioxide (CO2), both maintained at a bulk fluid temperature of 223 K. The study’s hypothesis proposes that, under the same boundary conditions and geometrical constraints, CO2 will show higher velocity, turbulent kinetic energy, vorticity, and convection currents than N2. This assumption is based on the premise that buoyancy forces in CO2 will dominate over viscous forces, leading to prominent convection currents.Comprehensive computational fluid dynamics (CFD) analysis using ANSYS software was employed to address this hypothesis. Transient simulations were conducted on a 2D domain, capturing the evolution of static temperature, velocity magnitude, turbulent kinetic energy, and vorticity with time. The results provided both visual and quantitative analyses to illustrate the dynamic convection currents being displayed as Bénard cells. The preliminary findings of this study confirmed the difference in the convection characteristics between N2 and CO2. CO2 exhibited higher velocity magnitude, increased turbulent kinetic energy, and more pronounced vorticity patterns. These results portray the dominant role of buoyancy forces in influencing convection and demonstrate the distinct behavior of these gases within the enclosure.The significance of this research extends to its potential implications for aerosol-cloud formation on diverse planetary bodies. Given the scarcity of experimental data on convection processes in space, the insights derived from this computational analysis contribute significantly to our understanding of these dynamics, offering valuable inputs for future research endeavors.
Funder Acknowledgement(s): Centers of Research Excellence in Science and Technology (CREST) REU program funded by the National Science Foundation under grant number HRD 1736136. NASA-JPL Planetary Cloud-Aerosol Research Facility (PCARF) for the assistance in running the simulations needed for this research.
Faculty Advisor: Stephen Akwaboa, stephen.akwaboa@sus.edu
Role: I performed the computational fluid dynamics analysis in ANSYS Fluent software, gathered and synthesised the data.