Simulations of 2D Turbulent Convection in a Density-Strati ed Fluid

High resolution computer simulations of two-dimensional convection using the anelastic approximation are presented. These calculations span Rayleigh numbers from 10 10 for Prandtl number equal to unity, with the uid density decreasing by a factor of 12 from the bottom to the top of the convection region. This range covers several decades in the \hard" turbulent regime. While many studies of this sort have been conducted for the Boussinesq approximation (i.e. no density strati cation), these are the rst to use the anelastic approximation with a signi cant density strati cation in this turbulent regime. The convection is dominated by a large scale coherent ow composed of ascending and descending superplumes. We nd a power law exponent of 0.28 for the NusseltRayleigh number scaling and a power law with exponent of 0.50 for the Reynolds-Rayleigh number scaling for the entire parameter space studied. These values are very similar to those determined experimentally and analytically for convection with no density strati cation.