This project will continue two unique research projects that investigate fundamental physics occurring in Earth's core. First, we will make novel measurements of turbulent convection that simulates Earth's core using the unique rotating magnetoconvection device that was designed and developed in our laboratory. In particular, we will carry out detailed measurements of turbulent convection, rotating convection, magnetoconvection and rotating magnetoconvection in liquid gallium. This data, providing the first measurements of strongly turbulent rotating magnetoconvection, will allow us to better understand the fundamental convection dynamics in core settings. Second, we will carry out quasigeostrophic two-dimensional numerical models and three-dimensional laboratory models of core convection influenced by core-mantle boundary (CMB) topography. These models will be used to determine how CMB topography can affect core flow patterns, how core-mantle torques are generated between the fluid and the topography, and at what height of topography core flow is significantly altered. This will be the first investigation covering a broad range of parameter values that will provide scaling laws for topographic interactions between the mantle and the core.
These studies will provide benchmark data describing rotating magnetoconvection and core-mantle coupling mechanisms. These results will be especially relevant to numerical modelers of the Earth's core and other planetary dynamos. They will also be relevant to geophysicists and geodesists who model Earth's rotational properties, astrophysical dynamo modelers, and fluid physicists and engineers studying convection physics and magnetohydrodynamics. These projects will provide computational and experimental training for undergraduate and graduate students in the laboratory. Furthermore, this funding will allow the development of a library of rotating fluid dynamics movies that will be available online for educators and students alike.
