Two-dimensional viscous accretion disk models. I - On meridional circulations in radiative regions
Two-dimensional viscous accretion disk models. I - On meridional circulations in radiative regions
复制标题
二维粘性吸积盘模型。
DOI：
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发表时间：
1992
期刊：
影响因子：
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通讯作者：
D. Lin
中科院分区：
文献类型：
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作者：
W. Kley;D. Lin
有人认为，薄开普勒磁盘，像旋转的恒星，不能达到流体静力学和热平衡同时，如果角速度是半径的函数。为了解决薄吸积盘的垂直结构和稳定性的问题，我们进行了二维轴对称计算，通过求解一组完全非线性流体动力学方程，包括辐射输运。结果表明，旋转速度随高度的变化太小，不能维持流体静力平衡。相反，径向（流入）速度随高度的变化足以建立一个稳定的状态。特别是，我们发现，对于较低的粘度参数α值，有大量的外流在中心部分的磁盘接近赤道平面，和流入仅在表面附近。只有当α值稍高时，整个圆盘中的流动才是向内的。因此，盘内的流动是粘性径向流入加上在中平面向外和在表面附近向内的循环流的结果。
It has been suggested that thin Keplerian disks, like rotating stars, cannot attain hydrostatic and thermal equilibrium simultaneously if the angular velocity is a function of radius only. To address the problem of vertical structure and stability of thin accretion disks, we performed 2D axisymmetric calculations by solving the set of fully nonlinear hydrodynamic equations, including radiation transport. The results indicate that the variation of the rotational velocity with height is too small to sustain hydrostatic equilibrium. Instead, the variation of the radial (inflow) velocity with height suffices to establish a stationary state. In particular, we find that for low values of the viscosity parameter alpha, there is mass outflow in the central parts of the disk close to the equatorial plane, and inflow only near the surface. Only for modestly high values of alpha, the flow throughout the disk is directed inward. Thus, the flow within the disk is the result of viscous radial inflow plus a circulatory flow directed outward in the midplane and inward near the surface.