混合长理论的湍流闭合
太阳与恒星天体物理
2018-09-28 v3 流体动力学
摘要
我们提出一种基于混合长理论、以三维涨落对二维背景的湍流闭合方法。该模型旨在可快速计算以植入恒星演化软件，并以单一自由参数（即混合长）捕捉广泛的相关现象。我们在具有非线性衰减的线性增长理论形式体系中精确纳入磁、转动、斜压与浮力效应。我们在共转系中以一种新颖的受控近似对差旋效应作微扰处理，该近似将参考系的时间演化匹配至任意阶。我们随后将此模型实现于一个高效开源代码中，并讨论所得的湍流应力与输运系数。我们展示该模型展现对流、斜压与剪切不稳定性以及磁转动不稳定性(MRI)。它还展现非线性饱和行为，我们借此提取各物理有趣极限下多种输运系数的渐近标度。
引用
@article{arxiv.1803.00579,
title = {Turbulence Closure for Mixing Length Theories},
author = {Adam S. Jermyn and Pierre Lesaffre and Christopher A. Tout and Shashikumar M. Chitre},
journal= {arXiv preprint arXiv:1803.00579},
year = {2018}
}
备注
17 pages, 20 figures, published in MNRAS. Figures 9-19 and C1 and associated text have been updated relative to MNRAS version to reflect minor changes due to corrections to the numerical code. Typographic errors have been corrected in equations 8, 10 and 11 and Figure 1 caption. Figure 3 legend updated to be clearer, and colors have been coordinated between Figures 1-3