P19 - DNS of Strongly Turbulent Thermal Convection in a Non-Rotating Full Sphere
DescriptionBody forces such as gravity can drive convective motion in fluids. Convection due to thermal gradients and the resulting buoyancy force is called thermal convection and occurs ubiquitously in nature. We present results on DNS of thermal convection in a non-rotating full sphere and with different boundary conditions, the Rayleigh and Prandtl numbers being the non-dimensional control parameters. We aim to characterise fluid flow and heat transfer in a wide range of parameters, using a global Reynolds number as a measure for the vigour of the flow and the Nusselt number quantifying the strength of heat advection as primary diagnostics. DNS are run up to a Rayleigh number appr. 10^8 times the critical Rayleigh at a Prandtl number of unity, yielding scaling relations between the diagnostics and Ra up to this regime of strong turbulence. The simulations were performed using the fully spectral, efficiently parallelised MHD/fluid dynamics code QuICC on CSCS's Daint cluster.
TimeTuesday, June 2719:30 - 21:30 CEST