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arXiv · 1111.3261

Improving smoothed particle hydrodynamics with an integral approach to calculating gradients

Domingo Garcia-Senz·Ruben M. Cabezon·Jose Antonio Escartin
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Abstract

In this paper we develop and test a fully conservative SPH scheme based on a tensor formulation that can be applied to simulate astrophysical systems. In the proposed scheme, derivatives are calculated from an integral expression that leads to a tensor (instead of a vectorial) estimation of gradients and reduces to the standard formulation in the continuum limit. The new formulation improves the interpolation of physical magnitudes, leading to a set of conservative equations that resembles those of standard SPH. The resulting scheme is verified using a variety of well-known tests, all of them simulated in two dimensions. We also discuss an application of the proposed tensor method to astrophysics by simulating the stability of a Sun-like polytrope calculated in three dimensions.

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Domingo Garcia-Senz, Ruben M. Cabezon, Jose Antonio Escartin. 2011-12-05. Improving smoothed particle hydrodynamics with an integral approach to calculating gradients. https://doi.org/10.1051/0004-6361%2F201117939

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