论文标题
完全保守的自我赋入流体动力学的雅典娜++框架的扩展
An Extension of the Athena++ Framework for Fully Conservative Self-Gravitating Hydrodynamics
论文作者
论文摘要
自我化流动流的数值模拟进化了动量方程和能量方程，该方程是由于时间依赖性的重力潜力而导致加速度和重力能量释放的能量方程。在这项工作中，我们在天体物理磁性水力学框架雅典娜++中实施了一种完全保守的数值算法，用于使用源术语来进行自我修剪流。我们证明，当正确评估的源术语与相应的“重力通量”（即引力应力张量或重力能量通量）的差异相同时，它们是保守的。我们提供了测试问题，这些问题证明了基于源期算法的几个优势，包括二阶收敛和圆形误差总动量和总能量保护。完全保守的方案抑制异常加速度在应用重力应力张量的常见数值离散化时会产生的异常加速度，该加速度无法保证无卷曲的重力。
Numerical simulations of self-gravitating flows evolve a momentum equation and an energy equation that account for accelerations and gravitational energy releases due to a time-dependent gravitational potential. In this work, we implement a fully conservative numerical algorithm for self-gravitating flows, using source terms, in the astrophysical magnetohydrodynamics framework Athena++. We demonstrate that properly evaluated source terms are conservative when they are equivalent to the divergence of a corresponding "gravity flux" (i.e., a gravitational stress tensor or a gravitational energy flux). We provide test problems that demonstrate several advantages of the source-term-based algorithm, including second order convergence and round-off error total momentum and total energy conservation. The fully conservative scheme suppresses anomalous accelerations that arise when applying a common numerical discretization of the gravitational stress tensor that does not guarantee curl-free gravity.
