Angular momentum transport and turbulence in laboratory models of Keplerian flows

¹ Department of Physics and Center for Nonlinear DynamicsUniversity of Texas, Austin, TX, 78712, USA
e-mail: mpaolett@gmail.com
² Physics of Fluids Group, Faculty of Science and Technology, Mesa+ Institute and Burgers Center for Fluid Dynamics, University of Twente, 7500AE Enschede, The Netherlands
³ CNRS URA 2464 SPHYNX/SPEC/IRAMIS/DSM, CEA Saclay, 91191 Gif-sur-Yvette, France
⁴ Departments of Physics and Geology, Institute for Research in Electronics and Applied Physics, Institute for Physical Science and Technology, University of Maryland, College Park, MD 20742, USA
e-mail: lathrop@umd.edu

Received: 23 November 2011
Accepted: 5 September 2012

Abstract

We present angular momentum transport (torque) measurements in two recent experimental studies of the turbulent flow between independently rotating cylinders. In addition to these studies, we reanalyze prior torque measurements to expand the range of control parameters for the experimental Taylor-Couette flows. We find that the torque may be described as a product of functions that depend only on the Reynolds number, which describes the turbulent driving intensity, and the rotation number, which characterizes the effects of global rotation. For a given Reynolds number, the global angular momentum transport for Keplerian-like flow profiles is approximately 14% of the maximum achievable transport rate. We estimate that this level of transport would produce an accretion rate of Ṁ/Ṁ₀~10^-3 in astrophysical disks. We argue that this level of transport from hydrodynamics alone could be significant. We also discuss the possible role of finite-size effects in triggering or sustaining turbulence in our laboratory experiments.