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Title: Simulation of Spheromak Evolution and Energy Confinement

Conference ·
DOI:https://doi.org/10.1063/1.1869501· OSTI ID:15011410

Simulation results are presented that illustrate the formation and decay of a spheromak plasma driven by a coaxial electrostatic plasma gun, and that model the energy confinement of the plasma. The physics of magnetic reconnection during spheromak formation is also illuminated. The simulations are performed with the three-dimensional, time-dependent, resistive magnetohydrodynamic NIMROD code. The simulation results are compared to data from the SSPX spheromak experiment at the Lawrence Livermore National Laboratory. The simulation results are tracking the experiment with increasing fidelity (e.g., improved agreement with measurements of the magnetic field, fluctuation amplitudes, and electron temperature) as the simulation has been improved in its representations of the geometry of the experiment (plasma gun and flux conserver), the magnetic bias coils, and the detailed time dependence of the current source driving the plasma gun, and uses realistic parameters. The simulations are providing a better understanding of the dominant physics in SSPX, including when the flux surfaces close and the mechanisms limiting the efficiency of electrostatic drive.

Research Organization:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Organization:
US Department of Energy (US)
DOE Contract Number:
W-7405-ENG-48
OSTI ID:
15011410
Report Number(s):
UCRL-CONF-207873; TRN: US0501392
Resource Relation:
Journal Volume: 12; Journal Issue: 5; Conference: Presented at: 46th Annual Meeting of the Division of Plasma Physics, Savannah, GA (US), 11/13/2004--11/19/2004; Other Information: PBD: 9 Nov 2004
Country of Publication:
United States
Language:
English

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