2005/01/21 by Banibrata Mukhopadhyay, Niayesh Afshordi, Mukhopadhyay, Banibrata +3 · 1 citation
Chemical Engineering · Engineering · Physics and Astronomy · #Astrophysics (astro-ph) #Astrophysics and Star Formation Studies #FOS: Physical sciences #Phase Equilibria and Thermodynamics #Thermodynamic properties of mixtures #astro-ph
paper · pdf · doi:10.48550/arxiv.astro-ph/0501468
6 pages including 5 figures. To appear in the proceedings of 22nd Texas Symposium on Relativistic Astrophysics, Stanford University, December 13-17, 2004
arxiv created 2005/01/21 · openalex publication_date 2005/01/21 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Turbulent viscosity in cold accretion disks is likely to be hydrodynamic in origin. We investigate the growth of hydrodynamic perturbations in a small region of a disk, which we model as a linear shear flow with Coriolis force, between two parallel walls. Although there are no exponentially growing eigenmodes in this system, because of the non-normal nature of the modes, it is possible to have a large transient growth in the energy of certain perturbations. For a constant angular momentum disk, the energy grows by more than a factor of 1000 for a Reynolds number of only 1000, and so turbulence is easily excited. For a Keplerian disk, the growth is more modest, and energy growth by a factor of 1000 requires a Reynolds number of nearly a million. Accretion disks have even larger Reynolds numbers than this. Therefore, transient growth of perturbations could seed turbulence in such disks.