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Plasma and Liquid Sodium Laboratory Dynamo Experiments at UW Madison

Posted on Jun 17, 2013 in GAFD 2013

Christopher Cooper (Univ. of Wisconsin - Madison)

First measurements of plasma temperature, density, and flow have been made on the Madison Plasma Dynamo Experiment (MPDX) that allow the particle and energy confinement as well as the plasma conductivity (η) and viscosity (ν) to be estimated. The MPDX is designed to create large flowing plasmas with high magnetic Reynolds number Rm = vL/η >> 1000, and an adjustable fluid Reynolds number 10 < Re = vL/ν < 1000, in the regime where the kinetic energy of the flow exceeds the magnetic energy (MA = v/vA >> 1). Simulations provide scenarios for generating large scale “slow” dynamos and small scale “fast” dynamos to be studied. Confinement is provided by alternating rings of 4 kG permanent magnets lining the vessel walls. Stirred is induced using anodes and thermally emissive Lanthanum hexaboride (LaB6) cathodes inserted in the confining magnetic multicusp edge of the plasma in a method first developed by the Plasma Couette Experiment (PCX) at UW Madison. An overview of plasma flows in PCX and MPDX will be presented as well as several experimental setups designed to achieve dynamo in MPDX. Resent results studying the vector turbulent EMF (the β effect) in the Madison Dynamo Experiment (MDE), a liquid sodium experiment at UW Madison will also be presented.