The hydrodynamical response of a tilted circumbinary disc: linear theory and non-linear numerical simulations
The hydrodynamical response of a tilted circumbinary disc: linear theory and non-linear numerical simulations
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倾斜环双星盘的流体动力学响应：线性理论和非线性数值模拟
DOI：
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发表时间：
1996
期刊：
影响因子：
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通讯作者：
J. Papaloizou
中科院分区：
文献类型：
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作者：
J. Larwood;J. Papaloizou
在本文中，我们提出了一个分析和数值研究的响应环双星盘的潮汐强迫的一个二进制与一个固定的圆形轨道。我们考虑流体盘的厚度范围和双星的质量比，轨道分离和倾角范围。我们的数值模拟使用SPH代码。对于我们的未扰动的光盘模型，我们写的剪切粘度的标度关系，并推导出光盘的厚度不能改变而不影响这些种SPH光盘模型的粘度。研究发现，由于圆盘的潮汐截断而产生的内腔的反引力对非零轨道倾角是有效的。此外，我们表明，我们的模型光盘可以进动近似像刚体，只要光盘是能够沟通的长度尺度可比的内边界半径由声波或粘性效应，在一个足够小的部分，当地的进动周期。此外，如果允许盘外缘变得任意大，则盘进动周期可能趋于无穷大，盘在内边界附近仅遭受适度的准稳态翘曲。当光盘响应是线性的，或弱非线性的，进动周期和形式的翘曲，我们测量产生合理的定量协议的分析表达式，我们从线性响应计算。对于更强的椎间盘反应，结果可能与我们的线性分析不一致，尽管反应的一些定性特征保持不变。我们表明，非相互作用的粒子的光盘的响应是定性的不同。本文所介绍的工作与当前人们感兴趣的星星和行星形成的一些天体物理现象有关。
In this paper we present an analytical and numerical study of the response of a circumbinary disc subject to the tidal-forcing of a binary with a fixed circular orbit. We consider fluid discs with a range of thicknesses and binaries with a range of mass ratios, orbital separations and inclination angles. Our numerical simulations are implemented using a SPH code. For our unperturbed disc models, we write a scaling relation for the shear viscosity and deduce that the disc thickness cannot be varied without affecting the viscosity in these kinds of SPH disc models. It is found that maintainance of an inner cavity owing to the tidal truncation of the disc is effective for non-zero orbital inclinations. Also we show that our model discs may precess approximately like rigid bodies, provided that the disc is able to communicate on a length scale comparable to the inner boundary radius by either sonic or viscous effects, in a sufficiently small fraction of the local precession period. Furthermore, the disc precession period may tend to infinity if the disc outer edge is allowed to become arbitrarily large, the disc suffering only a modest quasi-steady warp near the inner boundary. When the disc response is linear, or weakly non-linear, the precession periods and the forms of warping that we measure yield reasonable quantitative agreement with the analytical expressions that we derive from a linear response calculation. For a stronger disc response the results can agree poorly with our linear analysis, although some qualitative features of the response remain intact. We show that the response of a disc of non-interacting particles is qualitatively different from this. The work presented in this paper is of relevance to a number of astrophysical phenomena of current interest in star and planet formation.