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Ohlsen, Daniel R.

Publications and source records attributed to Ohlsen, Daniel R..

Experiment 7: The Geophysical Fluid Flow Cell Experiment on USML-2

The Geophysical Fluid Flow Cell (GFFC) experiment performed visualizations of thermal convection in a rotating differentially heated spherical shell of fluid. In these experiments dielectric polarization forces are used to generate a radially directed buoyancy force. This enables the laboratory simulation of a number of geophysically and astrophysically important situations in which sphericity and rotation both impose strong constraints on global scale fluid motions. During USML-2 a large set of experiments with spherically symmetric heating were carried out. These enabled the determination of critical points for the transition to various forms of non-axisymmetric convection and, for highly turbulent flows, the transition latitudes separating the different modes of motion. This paper presents a first analysis of these experiments as well as data on the general performance of the instrument during the USML-2 flight.

Hart, John E.↗

Waves in Radial Gravity Using Magnetic Fluid

We are beginning laboratory experiments using magnetically active ferrofluids to study surface waves in novel geometries. Terrestrial gravity is eliminated from the dynamics, and the magnetic body force felt by ferrofluid in the presence of a magnetic field gradient is used to create a geopotential field which is a section of or an entire sphere or cylinder. New optical, electromagnetic and ultrasonic diagnostic techniques are under development to initially study capillary-gravity wave propagation and interaction in such geometries.

Ohlsen, Daniel R.↗