首页> 外文期刊>The Astrophysical journal >Dynamics of the Transition from a Thin Accretion Disk to an Advection-dominated Accretion Flow
【24h】

Dynamics of the Transition from a Thin Accretion Disk to an Advection-dominated Accretion Flow

机译:从薄吸积盘到平流为主的吸积流过渡的动力学

获取原文
获取外文期刊封面目录资料

摘要

We consider an optically thin advection-dominated accretion flow (ADAF) that is connected at a finite transition radius to an outer optically thick, geometrically thin disk. We include turbulent energy transport and examine ADAF models that satisfy the following boundary conditions at the transition radius: (1) the temperature of the gas is much lower than the virial temperature, (2) the rotation is super-Keplerian, and (3) the net radial flux of energy is outward. We numerically solve the height-integrated viscous hydrodynamic equations with these boundary conditions. We find that the Bernoulli parameter is positive for a wide range of radius, indicating that outflows may be possible from ADAFs. Turbulent energy transport enhances the Bernoulli parameter. We compare our numerical global solutions with two published analytical solutions. We find that the solution of Honma represents the transition region well, while the self-similar solution of Narayan & Yi works better away from the transition. However, neither analytical solution is able to represent the density or angular momentum profile in the inner region of the ADAF, where the flow makes a sonic transition.
机译:我们考虑以光学上薄的对流为主的增生流(ADAF),该流以有限的过渡半径连接到外部的光学上厚的,几何上薄的磁盘。我们包括湍流能量传输,并研究在过渡半径处满足以下边界条件的ADAF模型:(1)气体温度远低于病毒温差;(2)旋转是超级开普勒式方程;以及(3)能量的净径向通量是向外的。在这些边界条件下,我们用数值方法求解了高度积分粘性流体力学方程。我们发现,伯努利参数在较大范围的半径内为正,表明ADAF可能流出。湍流的能量传输增强了伯努利参数。我们将数值全局解与两个已发布的解析解进行比较。我们发现,Honma的解很好地代表了过渡区域,而Narayan&Yi的自相似解在远离过渡的情况下效果更好。但是,这两种分析方法都不能代表流动发生声波转变的ADAF内部区域的密度或角动量分布。

著录项

获取原文

客服邮箱:kefu@zhangqiaokeyan.com

京公网安备:11010802029741号 ICP备案号:京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有
  • 客服微信

  • 服务号