2D Radiation MHD K-shell Modeling of Single Wire Array Stainless Steel Experiments on the Z Machine

Journal Article · Wed Jan 21 04:00:00 EST 2009 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.3079717· OSTI ID:21255328

Thornhill, J W; Giuliani, J L; Apruzese, J P; Chong, Y K; Davis, J; Dasgupta, A ^[1]; Whitney, K G; Clark, R W ^[2]; Jones, B; Coverdale, C A; Ampleford, D J; Cuneo, M E ^[3]; Deeney, C ^[4]

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1. Plasma Physics Division, Naval Research Laboratory, Washington DC 20375 (United States)
2. Berkeley Research Associates, Beltsville Maryland 20705 (United States)
3. Sandia National Laboratories, Albuquerque NM 87545 (United States)
4. National Nuclear Security Administration, Washington DC 20585 (United States)

Many physical effects can produce unstable plasma behavior that affect K-shell emission from arrays. Such effects include: asymmetry in the initial density profile, asymmetry in power flow, thermal conduction at the boundaries, and non-uniform wire ablation. Here we consider how asymmetry in the radiation field also contributes to the generation of multidimensional plasma behavior that affects K-shell power and yield. To model this radiation asymmetry, we have incorporated into the MACH2 r-z MHD code a self-consistent calculation of the non-LTE population kinetics based on radiation transport using multi-dimensional ray tracing. Such methodology is necessary for modeling the enhanced radiative cooling that occurs at the anode and cathode ends of the pinch during the run-in phase of the implosion. This enhanced radiative cooling is due to reduced optical depth at these locations producing an asymmetric flow of radiative energy that leads to substantial disruption of large initial diameter (>5 cm) pinches and drives 1D into 2D fluid (i.e., Rayleigh-Taylor like) flows. The impact of this 2D behavior on K-shell power and yield is investigated by comparing 1D and 2D model results with data obtained from a series of single wire array stainless steel experiments performed on the Z generator.

• OSTI ID: 21255328
• Journal Information: AIP Conference Proceedings, Journal Name: AIP Conference Proceedings Journal Issue: 1 Vol. 1088; ISSN 0094-243X; ISSN APCPCS
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ABLATION
ANODES
ASYMMETRY
CATHODES
IMPLOSIONS
K SHELL
MAGNETOHYDRODYNAMICS
PLASMA
PLASMA PRODUCTION
RADIATION TRANSPORT
RADIATIVE COOLING
SIMULATION
STAINLESS STEELS
THERMAL CONDUCTION
WIRES