热吸积流中径向粘滞力和各向异性热传导的作用

IF 1.9 4区 物理与天体物理 Q2 ASTRONOMY & ASTROPHYSICS
Maryam Ghasemnezhad , Mohsen Khosravi
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引用次数: 0

摘要

最近的观测证据证实,Sgr A∗ 和其他邻近星系核周围的热光学稀薄吸积流具有弱碰撞动力学。因此,热传导作为一种扩散过程,可以通过电子在无碰撞磁化等离子体中传递热量。以往的分析研究大多考虑方位粘度,而最近的研究表明,径向粘度对平流主导吸积盘的性质影响很大。因此,在本文中,我们通过考虑轴对称和稳态假设,探讨了热吸积盘中各向异性热传导(平行和垂直)和径向粘度两部分的作用。我们使用自相似解集来求解本模型的基本方程。我们的求解结果表明,横向热传导作为一种冷却机制,会导致气体温度、圆盘厚度和圆盘的吸积速度降低,而圆盘却在快速旋转。此外,我们的求解表明,垂直热传导和径向粘度在圆盘的物理变量中具有相反的行为。同时,我们的结果还表明,在满足物理约束条件 tin≥t⊥,con 和 q∥,con⩽q⊥,con 的区域,各向异性热传导在径向粘度、外流等参数空间中具有重要作用。
本文章由计算机程序翻译,如有差异,请以英文原文为准。
The role of radial viscosity force and anisotropic thermal conduction in hot accretion flow

Recent observational evidence confirms the weak-collision dynamics of hot optically thin accretion flows around Sgr A and other nearby galactic nuclei. As a result, thermal conduction as a diffusion process can transfer the heat by electrons in a collisionless magnetized plasma. While most of the previous analytical studies consider the azimuthal viscosity, the recent studies indicated that the radial viscosity strongly affects the properties of the advection dominated accretion discs. So, in this paper, we explore the roles of two parts of anisotropic thermal conduction (parallel and perpendicular) and radial viscosity in the hot accretion disc by considering axisymmetric and steady state assumptions in the presence of outflows that can transport energy from accretion disc outward. We use the set of self-similar solutions to solve the basic equations in our present model. Our solutions reveal that transverse thermal conduction as a cooling mechanism, leads to reductions in gas temperature, disc thickness, and accretion velocity of the disc, whereas the disc rotates at a fast rate. Moreover Our solutions indicate that the perpendicular thermal conduction and the radial viscosity have opposite behavior in the physical variables of the disc. Also, our results have indicated that the anisotropic thermal conduction is significant in the parameter space of radial viscosity, outflow in the regions that the physical constraints tint,con and q,conq,con are satisfied.

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来源期刊
New Astronomy
New Astronomy 地学天文-天文与天体物理
CiteScore
4.00
自引率
10.00%
发文量
109
审稿时长
13.6 weeks
期刊介绍: New Astronomy publishes articles in all fields of astronomy and astrophysics, with a particular focus on computational astronomy: mathematical and astronomy techniques and methodology, simulations, modelling and numerical results and computational techniques in instrumentation. New Astronomy includes full length research articles and review articles. The journal covers solar, stellar, galactic and extragalactic astronomy and astrophysics. It reports on original research in all wavelength bands, ranging from radio to gamma-ray.
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