Research Projects

Turbulent Rayleigh-Bernard (RB) convection is a critical system of thermally driven turbulence used in various applications, including the atmosphere, oceans, buildings, metallurgy, geophysical processes, and astrophysics. The system has two non-dimensional control parameters, the Rayleigh number Ra and Prandtl number P r, and two response parameters, the non-dimensional heat flux from bottom to top given by the Nusselt number N u and the extent of turbulence, the Reynolds number Re. Key issues in this application include scaling of heat flux (Nu) and turbulence (Re) in the ultimate-Ra regime, allowing extrapolations to the Ra regime in geophysical and astrophysical phenomena. The main scientific issues to be addressed in this proposal are related to the interactions between turbulence and thermal convection in the context of a RB convection problem and how to represent such interactions through accurate and HPC-optimized turbulence modeling approaches. The research will examine the existence of the ultimate Ra regime, the existence of a coherent large scale convection (LSC), the validity of the Oberbeck-Boussinesq (OB) assumption, and the aspect ratio dependence of flow and thermal characteristics. The proposed research will make a significant contribution to understanding thermally-driven turbulence in the ultimate Ra regime and improve the capability of computational modeling approaches like DNS and LES to efficiently resolve small-scale structures in boundary layer flows.