Distributed Implementation of Sph for Simulations of Accretion Disks
نویسنده
چکیده
We present a brief introduction to Smoothed Particle Hydrodynamics (SPH), where we focus on an approach to treat the physical viscosity. Additionally we describe in detail the basic principles of our parallel implementation of the SPH method. In the second part we summarise some results of test simulations performed to achieve general features of the method, and we end discussing some astrophysical applications, namely the simulation of accretion disks in Cataclysmic Variables. Smoothed Particle Hydrodynamics (SPH) is a grid-free Lagrangian method for solving the Navier-Stokes equations numerically. It was introduced in 1977 by Gingold & Monaghan 1 and by Lucy 2. The method is especially suited for compressible ows involving free boundaries, a commonplace situation in astrophysics. In SPH the matter distribution is divided into small overlapping mass packets, so-called particles, which do not exchange matter. The particles move in space following the motion of the uid while interacting with their neighbour particles. 1.1 Basic Principles The system of hydrodynamic equations, i. e., the Navier-Stokes equation, the equation of continuity, and the energy equation together with an equation of state, form a system of coupled partial diierential equations. Applying the SPH formalism, these are transformed into a set of ordinary diierential equations (ODEs) in two steps. These ODEs are subsequently integrated numerically using standard meth
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Distributed Implementation of Sph for Simulations of Accretion Disks
We present a brief introduction to Smoothed Particle Hydrodynamics SPH where we focus on an approach to treat the physical viscosity Additionally we describe in detail the basic principles of our parallel implementation of the SPH method In the second part we summarise some results of test simulations performed to achieve general features of the method and we end discussing some astrophysical a...
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