English
Related papers

Related papers: A self-similar solution for thermal disc winds

200 papers

Recent experiments on mucociliary clearance, an important defense against airborne pathogens, have raised questions about the topology of two-dimensional (2D) flows. We introduce a framework for studying ensembles of 2D time-invariant flow…

Fluid Dynamics · Physics 2024-12-30 M. Kamb , J. Byrum , G. Huber , G. Le Treut , S. Mehta , B. Veytsman , D. Yllanes

Context: Clumping in the radiation-driven winds of hot, massive stars arises naturally due to the strong, intrinsic instability of line-driving (the `LDI'). But LDI wind models have so far mostly been limited to 1D, mainly because of severe…

Solar and Stellar Astrophysics · Physics 2018-03-21 J. O. Sundqvist , S. P. Owocki , J. Puls

We consider the equation that models the spreading of thin liquid films of power-law rheology. In particular, we analyze the existence and uniqueness of source-type self-similar solutions in planar and circular symmetries. We find that for…

Mathematical Physics · Physics 2007-05-23 D. G. Aronson , S. I. Betelu , M. A. Fontelos , A. Sanchez

We present the two-dimensional inflow-outflow solutions of radiation hydrodynamic (RHD) equations of supercritical accretion flows. Compared with prior studies, we include all components of the viscous stress tensor. We assume steady state…

High Energy Astrophysical Phenomena · Physics 2020-01-15 Fatemeh Zahra Zeraatgari , Amin Mosallanezhad , Ye-Fei Yuan , De-Fu Bu , Liquan Mei

This paper shows that the topological structures of particle orbits generated by a generic class of vector fields on spherical surfaces, called {\it the flow of finite type}, are in one-to-one correspondence with discrete structures such as…

Dynamical Systems · Mathematics 2022-08-18 Takashi Sakajo , Tomoo Yokoyama

The work presented here focuses on the role of zonal flows in the self-sustenance of gravito-turbulence in accretion discs. The numerical analysis is conducted using a bespoke pseudo-spectral code in fully compressible, non-linear…

Solar and Stellar Astrophysics · Physics 2019-11-01 Riccardo Vanon

Observational evidence and theoretical arguments postulate that outflows may play a significant role in the advection-dominated accretion discs (ADAFs). While the azimuthal viscosity is the main focus of most previous studies in this…

High Energy Astrophysical Phenomena · Physics 2020-03-18 S. M. Ghoreyshi , M. Shadmehri

We obtain self-similar solutions that describe the dynamics of a self-gravitating, rotating, viscous system. We use simplifying assumptions; but explicitly include viscosity and the cooling due to the dissipation of energy. By assuming that…

Astrophysics · Physics 2009-11-07 Mohsen Shadmehri , Jamshid Ghanbari

Simulation of the dynamics of dust-gas circumstellar discs is crucial in understanding the mechanisms of planet formation. The dynamics of small grains in the disc is stiffly coupled to the gas, while the dynamics of grown solids is…

Earth and Planetary Astrophysics · Physics 2018-11-16 Olga P. Stoyanovskaya , Tatiana A. Glushko , Nikolay V. Snytnikov , Valeriy N. Snytnikov

We perform numerical analyses of the structure induced by gravitational instabilities in cooling gaseous accretion discs. For low enough cooling rates a quasi-steady configuration is reached, with the instability saturating at a finite…

Astrophysics · Physics 2009-11-13 Peter Cossins , Giuseppe Lodato , Cathie Clarke

We perform direct numerical simulations (DNS) of passive heavy inertial particles (dust) in homogeneous and isotropic two-dimensional turbulent flows (gas) for a range of Stokes number, ${\rm St} < 1$, using both Lagrangian and Eulerian…

Fluid Dynamics · Physics 2018-04-18 Dhrubaditya Mitra , Prasad Perlekar

An analytic model is proposed for non-radiating accretion flows accompanied by up or down winds in a global magnetic field. Physical quantities in this model solution are written in variable-separated forms, and their radial parts are…

Astrophysics · Physics 2009-11-07 Osamu Kaburaki

Observations of collimated outflows in young stellar objects indicate that several features of the jets can be understood by adopting the picture of a two-component outflow, wherein a central stellar component around the jet axis is…

Astrophysics · Physics 2009-11-13 T. Matsakos , K. Tsinganos , N. Vlahakis , S. Massaglia , A. Mignone , E. Trussoni

We have explored the structure of hot flow bathed in a general large-scale magnetic field. The importance of outflow and thermal conduction on the self-similar structure of a hot accretion flows has been investigated. We consider the…

High Energy Astrophysical Phenomena · Physics 2015-06-05 A. Mosallanezhad , M. Khajavi , S. Abbassi

Self-gravitating discs are believed to play an important role in astrophysics in particular regarding the star and planet formation process. In this context, discs subject to an idealized cooling process, characterized by a cooling…

Astrophysics of Galaxies · Physics 2021-04-20 Noé Brucy , Patrick Hennebelle

Shape Dynamics is a 3D conformally invariant theory of gravity which possesses a large set of solutions in common with General Relativity. When looked closely, these solutions are found to behave in surprising ways, so in order to probe the…

General Relativity and Quantum Cosmology · Physics 2016-09-14 Daniel C. Guariento , Flavio Mercati

Self-similar and semi-analytical solutions are found for the height-averaged equations govern the dynamical behavior of a polytropic, self-gravitating disk under the effects of winds, around the nascent object. In order to describe time…

Solar and Stellar Astrophysics · Physics 2015-06-11 Shahram Abbassi , Erfan Nourbakhsh , Mohsen Shadmehri

Numerical simulations of outflows formed during the collapse of 100 M_sun cloud cores are presented. We derive a generalised criterion from MHD wind theory to analyse the launching mechanism of these outflows. The criterion is successfully…

Solar and Stellar Astrophysics · Physics 2015-05-30 D. Seifried , R. E. Pudritz , R. Banerjee , D. Duffin , R. S. Klessen

The classical problem of steady rarefied gas flow past an infinitely thin circular disk is revisited, with particular emphasis on the gas behavior near the disk edge. The uniform flow is assumed to be perpendicular to the disk surface. An…

Fluid Dynamics · Physics 2026-01-26 Takuma Tomita , Satoshi Taguchi , Tetsuro Tsuji

We report on a series of fully resolved simulations of the flow around a rigid sphere translating steadily near a wall, either in a fluid at rest or in the presence of a uniform shear. Non-rotating and freely rotating spheres subject to a…

Fluid Dynamics · Physics 2021-08-17 Pengyu Shi , Roland Rzehak , Dirk Lucas , Jacques Magnaudet