ar X iv : a st ro - p h / 93 10 02 4 v 1 1 3 O ct 1 99 3 An Owner ’ s Guide to Smoothed Particle Hydrodynamics
نویسندگان
چکیده
We present a practical guide to Smoothed Particle Hydro-dynamics (SPH) and its application to astrophysical problems. Although remarkably robust, SPH must be used with care if the results are to be meaningful since the accuracy of SPH is sensitive to the arrangement of the particles and the form of the smoothing kernel. In particular, the initial conditions for any SPH simulation must consist of particles in dynamic equilibrium. We describe some of the numerical difficulties that may be encountered when using SPH, and how these may be overcome. Through our experience in using SPH code to model convective stars, galaxy clusters and large scale structure problems we have developed many diagnostic tests. We give these here as an aid to rapid identification of errors, together with a list of basic prerequisites for the most efficient implementation of SPH.
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