The fundamental difference between shear alpha viscosity and turbulent magnetorotational stresses
The fundamental difference between shear alpha viscosity and turbulent magnetorotational stresses
复制标题
剪切α粘度和湍流磁转应力之间的根本区别
DOI：
10.1111/j.1365-2966.2007.12574.x
复制
发表时间：
2006
影响因子：
4.8
通讯作者：
D. Psaltis
中科院分区：
文献类型：
--
作者：
M. Pessah;Chi;D. Psaltis
由磁旋转不稳定性 (MRI) 驱动的湍流、磁化、差动旋转流的数值模拟通常用于计算吸积盘分析模型中调用的 α 粘度的有效值。在本文中，我们使用湍流磁流体动力应力的各种动力学模型以及剪切盒的数值模拟来表明，MRI驱动的吸积盘中的角动量传输不能用剪切粘度的标准模型来描述。特别是，我们证明了湍流磁旋转应力与局部剪切力不成线性比例，并且对于向外增加的角速度分布同样消失。
Numerical simulations of turbulent, magnetized, differentially rotating flows driven by the magnetorotational instability (MRI) are often used to calculate the effective values of alpha viscosity that is invoked in analytical models of accretion discs. In this paper, we use various dynamical models of turbulent magnetohydrodynamic stresses, as well as numerical simulations of shearing boxes, to show that angular momentum transport in MRI-driven accretion discs cannot be described by the standard model for shear viscosity. In particular, we demonstrate that turbulent magnetorotational stresses are not linearly proportional to the local shear and vanish identically for angular velocity profiles that increase outwards.
DOI：
10.1086/382184
发表时间：
2003-12
期刊：
The Astrophysical Journal
影响因子：
--
作者：
T. Sano;S. Inutsuka;N. Turner;J. Stone
通讯作者：
T. Sano;S. Inutsuka;N. Turner;J. Stone