10:34 AM–12:44 PM, Sunday, November 18, 2007
Salt Palace Convention Center - 250 F
Chair: H.J.S. Fernando, Arizona State University
Abstract ID: BAPS.2007.DFD.BL.9
12:18 PM–12:31 PM
Douglas H. Kelley
(University of Maryland)
Daniel S. Zimmerman
(University of Maryland)
Santiago Andres Triana
(University of Maryland)
Daniel P. Lathrop
(University of Maryland)
We present experimental studies of fluid flow in a spherical vessel with either shear- or propeller-driven flows. Our work is motivated by the numerical results of Dudley and James (1989), who found dynamo action in flows of this geometry (so-called S$_1$T$_1$ flow). Using liquid sodium as a test fluid, we apply an external magnetic field (up to 400~G) and image the induced field with an array of Hall probes near the surface of the vessel. A rich variety of dynamics occur at various rotation rates, including oscillatory behaviors, likely to be indicative of inertial waves in shear-driven flow or magnetocoriolis (MC) waves in propeller-driven flow. The detailed characteristics and dynamics of these waves, as well as their interaction with a turbulent (Re $\sim 10^7$) background flow, are the subject of ongoing research. Our work has implications for dynamo action, thought to produce the magnetic fields of stars, accretion disks, and planets, including Earth.
To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2007.DFD.BL.9