A High‐Resolution Adaptive Moving Mesh Hydrodynamic Algorithm

An algorithm for simulating self-gravitating cosmological astrophysical uids is presented. The advantages include a large dynamic range, parallelizability, high resolution per grid element, and fast execution speed. The code is based on a nite volume ux-conservative total variation diminishing (TVD) scheme for the shock-capturing hydro and an iterative multigrid solver for the gravity. The grid is a timedependent eld, whose motion is described by a generalized potential ow. Approximately constant mass per cell can be obtained, which provides all the advantages of a Lagrangian scheme. The grid deformation combined with appropriate limiting and smoothing schemes guarantees a regular and well-behaved grid geometry, in which nearest neighbor relationships remain constant. The full hydrodynamic uid equations are implemented in the curvilinear moving grid, which allows for arbitrary uid ow relative to the grid geometry. This combination retains all the advantages of the grid-based schemes including high speed per uid element and a rapid gravity solver.