论文标题
用颗粒建模天体物理流体
Modelling astrophysical fluids with particles
论文作者
论文摘要
计算流体动力学是理论上探索宇宙的关键工具。在过去的十年中，我们看到了实质性的方法论多样化，并在最初不同的方法之间进行了许多交叉施肥。在这里，我们关注与平滑颗粒流体动力学（SPH）方法有关的最新发展。我们简要总结了SPH诉求本身的最新技术改进，包括平滑内核，梯度计算和耗散转向。这些元素已在牛顿高准确性SPH Code Magma2中实现，我们在许多具有挑战性的基准测试中证明了其性能。再过一步，我们也使用了第一个基于粒子的一般性流体动力学代码中的这些新成分，该代码求解了整个爱因斯坦方程phincs_bssn。我们介绍了基本的思想和方程式，并以相对论中子恒星的示例与时空相对演变。
Computational fluid dynamics is a crucial tool to theoretically explore the cosmos. In the last decade, we have seen a substantial methodological diversification with a number of cross-fertilizations between originally different methods. Here we focus on recent developments related to the Smoothed Particle Hydrodynamics (SPH) method. We briefly summarize recent technical improvements in the SPH-approach itself, including smoothing kernels, gradient calculations and dissipation steering. These elements have been implemented in the Newtonian high-accuracy SPH code MAGMA2 and we demonstrate its performance in a number of challenging benchmark tests. Taking it one step further, we have used these new ingredients also in the first particle-based, general-relativistic fluid dynamics code that solves the full set of Einstein equations, SPHINCS_BSSN. We present the basic ideas and equations and demonstrate the code performance at examples of relativistic neutron stars that are evolved self-consistently together with the spacetime.
