Geophysics and Tectonics Seminar fall-2020

The Earth's molten outer core and its magnetic dynamo are prevalent geophysical characteristics that exist among many planets in the solar system and other planetary systems. Turbulent flows in the Earth's molten outer core, driven by convection, generate a planetary-scale, nearly axial, and dipole-dominated magnetic field. The behaviors of strongly turbulent convection in the presence of strong Lorentz forces are mostly unknown. Thus, we present results of laboratory experiments on heat transfer of non-rotating Rayleigh-Bénard convection of liquid gallium in the presence of a vertical magnetic field. The experiment is carried out in two cylindrical containers with diameter-to-height aspect ratio Gamma = 1 and 2 for 10^ 6 <~ Ra <~ 10^8 and 0 <~ Ch <~ 10^5. Combined with the results from the previous studies, our experiment shows a more complete picture of near-onset to supercritical behaviors of heat transfer in liquid metal magnetoconvection (MC) over a large range of parameter space (10^ 3 <~ Ra <~ 10^9).