First identification of sub- and supercritical convection patterns from ‘GeoFlow’, the geophysical flow simulation experiment integrated in Fluid Science Laboratory

Sheet-like and plume-like thermal flow in a spherical convection experiment performed under microgravity

“…In Travnikov et al (2003 and Feudel et al (2011), we have extensively applied the code to ideal isoviscous fluids with γ = 1. We summarize the most important results of Futterer et al (2010) with a focus on the agreement with the experimental data, and those of Feudel et al (2011) with the bifurcation scenario resulting from path following analysis in numerical simulations.…”

Thermal convection in a cylindrical annulus under a combined effect of the radial and vertical gravity

“…∂θ ∂t + u· ∇θ = 1 Pr θ (5) ∇· (1 − γ e θ) ∇φ = 0, E = − ∇φ (6) where Pr = ν/κ is the Prandtl number, Gr = α T Gd 3 /(ν 2 ) is the Grashof number (G = g in the gravity phase and G = 1.8 g in the hypergravity phase), T = T 1 − T 2 , γ a = α T is the thermal expansion parameter, γ e = T is the thermoelectric…”

“…In particular, it was that the dielectrophoretic force can be used to increase the heat transport in cylindrical systems [3,4]. The generation of convective motions by the dielectrophoretic force has been successfully tested in the GEOFLOW experiments that were performed in the Fluid Science Laboratory of the International Space Station where thermal convection patterns have been observed in a differentially rotating spherical shell submitted to a dielectrophoretic force [5,6]. Preliminary observations of the dielectrophoretic force effects in the cylindrical annulus were performed in parabolic flight experiments [7,8] where non-axisymmetric patterns were identified.…”

Traveling waves in low and intermediate rotating spherical shell convection

“…Here we use a Wollaston shearing interferometry, which, basically, is sensitive to gradients of the refractive index. The measurement images themselves show interference fringes, which correspond to the radially integrated temperature field (Futterer et al, 2010). Those images are construed in space and time in a more qualitative way, here.…”

“…The geometrical and physical properties, discussed with the radius ratio η = r i /r o and the Prandlt number P r = ν/κ, respectively, are fixed with η = 0.5 and P r = 64.64. Refer to von Larcher et al (2008) and Futterer et al (2010) for a detailed description of experiment parameters including the geometric dimensions as well as the physical properties of the working fluid, which is a silicone oil of viscosity ν, relative permittivity r and coefficient of dielectric expansion γ. Therewith fluid dynamics of 'GeoFlow' is described at sets of:…”