SPHINCS_BSSN: a general relativistic smooth particle hydrodynamics code for dynamical spacetimes
SPHINCS_BSSN: a general relativistic smooth particle hydrodynamics code for dynamical spacetimes
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SPHINCS_BSSN：动态时空的广义相对论光滑粒子流体动力学代码
DOI：
10.1088/1361-6382/abee65
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发表时间：
2020
影响因子：
3.5
通讯作者：
P. Diener
中科院分区：
文献类型：
--
作者：
S. Rosswog;P. Diener
我们提出了一种模拟自引力广义相对论流体的新方法。在我们的方法中，流体是在广义相对论(GR)光滑粒子流体动力学(SPH)的框架下通过拉格朗日粒子来模拟的，而时空是根据在欧拉GR流体力学中经常使用的Baumgarte-Shapiro-Shibata-Nakamura(BSSN)公式在网格上演化的。据我们所知，这是第一个拉格朗日完全广义相对论流体力学程序(所有以前的SPH方法都使用GR引力的近似)。我们的粒子网格方法的一个核心成分是气体(由粒子表示)和时空(由网格表示)之间的耦合，为此，我们开发了一套复杂的内插工具，这些工具受到其他粒子网格方法的启发，特别是涡旋粒子方法。在物质和时空之间划分方法的一个好处是，它给了我们更多选择分辨率的自由，这样--如果时空足够平滑--我们已经用适度数量的网格单元获得了很好的结果，并可以将计算精力集中在对物质的模拟上。我们方法的另一个优点是可以很容易地追踪到抛射物，而且中子星表面仍然很好，不需要任何特殊的处理。在程序的流体力学部分，我们使用了一些对SPH来说是新的技术，例如重建、坡度限制和通过监测熵守恒来引导耗散。在这里，我们详细描述了所采用的数值方法，并在一些基准问题中展示了代码的性能，从激波管测试、过考林近似到中子星在自洽演化的时空中的完全动力学演化。
We present a new methodology for simulating self-gravitating general-relativistic fluids. In our approach the fluid is modelled by means of Lagrangian particles in the framework of a general-relativistic (GR) smoothed particle hydrodynamics (SPH) formulation, while the spacetime is evolved on a mesh according to the Baumgarte–Shapiro–Shibata–Nakamura (BSSN) formulation that is also frequently used in Eulerian GR-hydrodynamics. To the best of our knowledge this is the first Lagrangian fully general relativistic hydrodynamics code (all previous SPH approaches used approximations to GR-gravity). A core ingredient of our particle–mesh approach is the coupling between the gas (represented by particles) and the spacetime (represented by a mesh) for which we have developed a set of sophisticated interpolation tools that are inspired by other particle–mesh approaches, in particular by vortex-particle methods. One advantage of splitting the methodology between matter and spacetime is that it gives us more freedom in choosing the resolution, so that—if the spacetime is smooth enough—we obtain good results already with a moderate number of grid cells and can focus the computational effort on the simulation of the matter. Further advantages of our approach are the ease with which ejecta can be tracked and the fact that the neutron star surface remains well-behaved and does not need any particular treatment. In the hydrodynamics part of the code we use a number of techniques that are new to SPH, such as reconstruction, slope limiting and steering dissipation by monitoring entropy conservation. We describe here in detail the employed numerical methods and demonstrate the code performance in a number of benchmark problems ranging from shock tube tests, over Cowling approximations to the fully dynamical evolution of neutron stars in self-consistently evolved spacetimes.
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影响因子：
5
作者：
Amit Poudel;W. Tichy;B. Brügmann;T. Dietrich
通讯作者：
Amit Poudel;W. Tichy;B. Brügmann;T. Dietrich
影响因子：
56.9
作者：
Hallinan, G.;Corsi, A.;Singer, L. P.
通讯作者：
Singer, L. P.
DOI：
10.1111/j.1365-2966.2012.21859.x
发表时间：
2012-11-01
影响因子：
4.8
作者：
Korobkin, O.;Rosswog, S.;Winteler, C.
通讯作者：
Winteler, C.
影响因子：
8.6
作者：
Abbott, B. P.;Abbott, R.;Zweizig, J.
通讯作者：
Zweizig, J.