The geoflow-experiment on ISS (part I): Experimental preparation and design of laboratory testing hardware Original Research Article

Thermal convection in a spherical shell represents an important model in fluid dynamics and geophysics. Investigations on thermal convective instabilities occuring in the spherical gap flow under terrestrial conditions are of basic importance especially for the understanding of symmetry-breaking bifurcations during the transition to chaos. Microgravity,experiments on thermal convection with a simulated central force field are important for the understanding of large scale geophysical motions as the convective transport phenomena in the Earthʹs liquid outer core. This report summarizes the concurrent experimental (part I), numerical (part II) and theoretical (part III) studies for the preparation of an International Space Station (ISS) experiment inside the Fluid Science Laboratory (FSL). This special experimental device with respect to geophysical simulations is called GEOFLOW. A central symmetric force field similar to the gravity field acting on planets can be produced using the effect of the dielectrophoretic force field by applying a high voltage potential difference to the inner and outer sphere. Flow visualization, Wollaston Shearing Interferometry and Laser Doppler Velocimetry will be used to determine the expected flow pattern during the space experiments.