ASTROPHYSICAL FLUID DYNAMICS VIA DIRECT STATISTICAL SIMULATION

Abstract

In this paper we introduce the concept of Direct Statistical Simulation (DSS)\nfor astrophysical flows. This technique may be appropriate for problems in\nastrophysical fluids where the instantaneous dynamics of the flows are of\nsecondary importance to their statistical properties. We give examples of such\nproblems including mixing and transport in planets, stars and disks. The method\nis described for a general set of evolution equations, before we consider the\nspecific case of a spectral method optimised for problems on a spherical\nsurface. The method is illustrated for the simplest non-trivial example of\nhydrodynamics and MHD on a rotating spherical surface. We then discuss possible\nextensions of the method both in terms of computational methods and the range\nof astrophysical problems that are of interest.\n