[M-IS12] Geophysical fluid dynamics-Transfield approach to geoscience

[MIS12-01] Heat transport and mixing in extremely confined Rayleigh-Bénard convection

*Daisuke Noto¹, Hugo N Ulloa¹, Juvenal A Letelier² (1.University of Pennsylvania, 2.Universidad de Chile)

Keywords:Thermal convection, Heat transport, Mixing, Hele-Shaw

Thermally driven flows in strongly confined environments, such as permeable media, are ubiquitous in nature. They contribute to the heat transfer across the Earth’s lithosphere and fluid mixing process within aquifers. The Hele-Shaw system is a laboratory analog for such geometrically constrained convective flows. In this work, we study heat transport and mixing characteristics of thermal convection in Hele-Shaw systems through laboratory experiments. Transparent fluid layers built for the laboratory experiments allow elucidation of velocity fields, and heat distributions were obtained for quasi-steady states throughout the heat equation. The experimental results are partially in agreement with the theoretical and numerical ones, except for the high Rayleigh-Darcy number at which the system becomes three-dimensional. We will discuss the flow features, heat transport characteristics, and mixing efficiency of thermal convection in extremely confined domains, covering Darcy, Hele-Shaw (quasi-two-dimensional), and three-dimensional regimes.