对于有限体积辐射-水力动力学而言,一个非对称正确的隐式-显式时间集成方案
Chong-Chong He1, Benjamin D Wibking2, Mark R Krumholz1,3
1Research School of Astronomy and Astrophysics, Australian National University, Canberra, ACT 2611, Australia.
概括
我们开发了一种新的辐射-水力学 (RHD) 数值方法,可以准确模拟复杂的天体物理流. 这种隐式-显式方案对于并行计算和自适应网状精细化是有效的.
科学领域:
- 天体物理流体动力学
- 计算物理学的计算物理.
- 数字方法 数字方法.
背景情况:
- 辐射水力学 (RHD) 模拟在计算上是密集的,因为时间尺度和过程重要性存在巨大差异.
- 现有的数值方法很难有效地处理这些跨计算领域的广泛范围.
研究的目的:
- 为非相对论RHD引入一种新的隐式-显式数值方法.
- 为了应对在RHD模拟中广泛的时间尺度和不同的过程重要性所带来的挑战.
- 开发一种适合现代高性能计算架构的方法.
主要方法:
- 开发了一个基于时刻的隐式-显式RHD方案.
- 确保机器精确度的能量和动量保存.
- 在GPU加速的RHD代码中实现了该方法,quokka.
主要成果:
- 该方法实现了机器精确的能量和动量保存.
- 它需要最小的通信,适合大规模并行和GPU系统.
- 在流式,静态扩散,动态扩散和非对称扩散模式中证明了非对称的准确性.
- 成功通过了广泛的数值测试.
结论:
- 新的隐式-显式RHD方法为复杂的天体物理模拟提供了强大而高效的解决方案.
- 它的设计使其非常适合适应性网状精细化和大规模并行计算环境.
- 该方法准确地处理各种物理状态,包括未解决的光子无平均值路径.
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