Phenomenological modeling of turbulence in Z-pinch implosions

Journal Article · Mon Jan 31 23:00:00 EST 1994 · Physics of Plasmas; (United States)

DOI:https://doi.org/10.1063/1.870834· OSTI ID:6641225

Thornhill, J W; Whitney, K G ^[1]; Deeney, C; LePell, P D ^[2]

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1. Plasma Physics Division, Naval Research Laboratory, Washington, D.C. 20375 (United States)
2. Physics International Inc., San Leandro, California 94577 (United States)

A phenomenological investigation into the effects of magnetohydrodynamic (MHD) turbulence on the initial stagnation dynamics of aluminum wire array and argon gas puff Z-pinch implosions is performed. The increases that turbulence produces in the plasma viscosity, heat conductivity, and electrical resistivity are modeled by using multipliers for these quantities in one-dimensional (1-D) MHD calculations. The major effect of these increases is to soften the 1-D implosions by decreasing the densities that are achieved on axis at stagnation. As a consequence, a set of multipliers can be found that reasonably duplicates the average electron temperatures, ion densities, and mass of the [ital K]-shell emission region that were measured at stagnation for a variety of Physics International aluminum wire array and argon gas puff experiments. It is determined that the dependence of these measured quantities on the multipliers is weak once a level of enhancement is reached, where agreement between calculations and experiments is attained. The scaling of [ital K]-shell yield with load mass for a fixed implosion velocity is then reexamined, and the minimum load mass needed to efficiently produce [ital K]-shell emission by thermalization of kinetic energy is calculated for aluminum and argon using this phenomenological soft implosion modeling. The results show an upward shift in the minimum mass by a factor of 6 when compared to the original nonturbulent hard implosion calculations.

• OSTI ID: 6641225
• Journal Information: Physics of Plasmas; (United States), Journal Name: Physics of Plasmas; (United States) Vol. 1:2; ISSN PHPAEN; ISSN 1070-664X
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700340* -- Plasma Waves
Oscillations
& Instabilities-- (1992-)
ALUMINIUM
ARGON
ELECTRON TEMPERATURE
ELECTRONIC STRUCTURE
ELEMENTS
FLUID MECHANICS
FLUIDS
GASES
HYDRODYNAMICS
IMPLOSIONS
ION DENSITY
K SHELL
MAGNETOHYDRODYNAMICS
MECHANICS
METALS
NONMETALS
ONE-DIMENSIONAL CALCULATIONS
PINCH DEVICES
PINCH EFFECT
RARE GASES
SCALING LAWS
THERMONUCLEAR DEVICES
TURBULENCE