A NUMERICAL ALGORITHM FOR GEOPHYSICAL AND ASTROPHYSICAL INHOMOGENEOUSFLUID-FLOWS

We present a 3-dimensional explicit high accuracy numerical code for t he solution of the Navier-Stokes equations in the Boussinesq approxima tion. The code is conceived to investigate inhomogeneous fluid flow ch aracterized by the presence of nonlinear interactions and of very stro ng gradients of the physical fields delocalized in the inhomogeneous d irection. In the linear regime the code has been tested by solving the well-known convective instability problem for which analytical soluti ons are available. To check its correctness and the stability in the n onlinear regime, we have solved the temporal mixing layer problem and reproduced results well established in the current literature. The cod e is optimized for massively parallel computers.