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This study investigates the spatial distribution of inertial particles in turbulent Taylor-Couette flow. Direct numerical simulations are performed using a one-way coupled Eulerian-Lagrangian approach, with a fixed inner wall Reynolds…

Fluid Dynamics · Physics 2024-02-28 Hao Jiang , Zhi-ming Lu , Bo-fu Wang , Xiao-hui Meng , Jie Shen , Kai Leong Chong

We study liquid-liquid dispersions in a turbulent Taylor-Couette flow, produced between two counterrotating coaxial cylinders. In pure Water and in counterrotation, Reynolds numbers up to 1.4 10^5 are reached. The liquids we use are a…

Fluid Dynamics · Physics 2008-06-20 Florent Ravelet , Rene Delfos , Jerry Westerweel

We use smoothed particle hydrodynamics simulations of massive protostellar discs to investigate the predicted broadening of molecular lines from discs in which self-gravity is the dominant source of angular momentum transport. The…

Solar and Stellar Astrophysics · Physics 2015-06-11 Duncan H. Forgan , Philip J. Armitage , Jacob B. Simon

Direct numerical simulations are used to investigate the individual dynamics of large spherical particles suspended in a developed homogeneous turbulent flow. A definition of the direction of the particle motion relative to the surrounding…

Fluid Dynamics · Physics 2015-06-16 Mamadou Cisse , Holger Homann , Jeremie Bec

We investigate the quasi two-dimensional Taylor-Couette system in the regime where the radius ratio is close to unity - a transitional regime between three and two dimensions. By systematically increasing the Reynolds number we observe a…

Fluid Dynamics · Physics 2015-12-02 Sebastian Altmeyer , Younghae Do , Ying-Cheng Lai

Experiments in a modified Taylor-Couette device, spanning Reynolds numbers of $10^5$ to greater than $10^6$, reveal the nonlinear stability of astrophysically-relevant flows. Nearly ideal rotation, expected in the absence of axial…

Instrumentation and Methods for Astrophysics · Physics 2014-03-04 Eric M. Edlund , Hantao Ji

The torque in turbulent Taylor-Couette flows for shear Reynolds numbers Re_S up to 3x10^4 at various mean rotations is studied by means of direct numerical simulations for a radius ratio of \eta=0.71. Convergence of simulations is tested…

Fluid Dynamics · Physics 2015-06-05 Hannes Brauckmann , Bruno Eckhardt

We study the turbulence induced in the dust layer of a protoplanetary disk based on the energetics of dust accretion due to gas drag. We estimate turbulence strength from the energy supplied by dust accretion, using the radial drift…

Earth and Planetary Astrophysics · Physics 2015-05-30 Taku Takeuchi , Takayuki Muto , Satoshi Okuzumi , Naoki Ishitsu , Shigeru Ida

We study the driving of turbulence in star-froming disc galaxies of different masses at different epochs, using an analytic "bathtub" model. The disc of gas and stars is assumed to be in marginal Toomre instability. Turbulence is assumed to…

Astrophysics of Galaxies · Physics 2022-06-07 Omri Ginzburg , Avishai Dekel , Nir Mandelker , Mark R. Krumholz

The statistics of velocity fluctuations of turbulent Taylor-Couette flow are examined. The rotation rate of the inner and outer cylinder are varied while keeping the Taylor number fixed to $1.49 \times 10^{12}$…

Fluid Dynamics · Physics 2015-06-16 Sander G. Huisman , Detlef Lohse , Chao Sun

The driving of turbulence in galaxies is deeply connected with the physics of feedback, star formation, outflows, accretion, and radial transport in disks. The velocity dispersion of gas in galaxies therefore offers a promising…

We investigate the nonlinear dynamics of turbulent shear flows, with and without rotation, in the context of a simple but physically motivated closure of the equation governing the evolution of the Reynolds stress tensor. We show that the…

Astrophysics · Physics 2009-11-10 Pascale Garaud , Gordon I. Ogilvie

A major uncertainty in accretion disk theory is the nature and properties of gas turbulence, which drives transport in protoplanetary disks. The commonly used viscous prescription for the Maxwell-Reynolds stress tensor gives rise to a…

Earth and Planetary Astrophysics · Physics 2015-06-12 Emmanuel Jacquet

The arising of turbulence in gas-dynamic (non-magnetic) accretion disks is a major issue of modern astrophysics. Such accretion disks should be stable against the turbulence generation, in contradiction to observations. Searching for…

Solar and Stellar Astrophysics · Physics 2014-10-01 E. P. Kurbatov , D. V. Bisikalo , P. V. Kaygorodov

We explore the gravitational instability of clumpy and turbulent gas discs, taking into account the Larson-type scaling laws observed in giant molecular clouds (GMCs) and HI, as well as more general scaling relations. This degree of freedom…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Alessandro B. Romeo , Andreas Burkert , Oscar Agertz

The velocity fluctuations in a spherical shell arising from sinusoidal perturbations of a Keplerian shear flow with a free amplitude parameter \epsilon are studied numerically by means of fully 3D nonlinear simulations. The investigations…

Astrophysics · Physics 2009-11-06 G. Rudiger , A. Drecker

Rayleigh-Benard convection and Taylor-Couette flow are two canonical flows that have many properties in common. We here compare the two flows in detail for parameter values where the Nusselt numbers, i.e. the thermal transport and the…

Fluid Dynamics · Physics 2017-04-12 Hannes Brauckmann , Bruno Eckhardt , Joerg Schumacher

The transition to turbulence in Taylor-Couette flow often occurs via a sequence of supercritical bifurcations to progressively more complex, yet stable, flows. We describe a subcritical laminar-turbulent transition in the counter-rotating…

(abridged) Context: Turbulent diffusion of large-scale flows and magnetic fields play major roles in many astrophysical systems. Aims: Our goal is to compute turbulent viscosity and magnetic diffusivity, relevant for diffusing large-scale…

Solar and Stellar Astrophysics · Physics 2020-04-29 Petri J. Käpylä , Matthias Rheinhardt , Axel Brandenburg , Maarit J. Käpylä

We numerically simulate turbulent Taylor-Couette flow for independently rotating inner and outer cylinders, focusing on the analogy with turbulent Rayleigh-B\'enard flow. Reynolds numbers of $Re_i=8\cdot10^3$ and $Re_o=\pm4\cdot10^3$ of the…