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Title: Computational modeling of Krypton gas puffs with tailored mass density profiles on Z

Abstract

Large diameter multi-shell gas puffs rapidly imploded by high current (∼20 MA, ∼100 ns) on the Z generator of Sandia National Laboratories are able to produce high-intensity Krypton K-shell emission at ∼13 keV. Efficiently radiating at these high photon energies is a significant challenge which requires the careful design and optimization of the gas distribution. To facilitate this, we hydrodynamically model the gas flow out of the nozzle and then model its implosion using a 3-dimensional resistive, radiative MHD code (GORGON). This approach enables us to iterate between modeling the implosion and gas flow from the nozzle to optimize radiative output from this combined system. Guided by our implosion calculations, we have designed gas profiles that help mitigate disruption from Magneto-Rayleigh–Taylor implosion instabilities, while preserving sufficient kinetic energy to thermalize to the high temperatures required for K-shell emission.

Authors:
; ; ; ; ; ; ; ; ; ;  [1]
  1. Sandia National Laboratories, PO Box 5800, Albuquerque, New Mexico 87185 (United States)
Publication Date:
OSTI Identifier:
22410412
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 22; Journal Issue: 5; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; COMPUTERIZED SIMULATION; DENSITY; GAS FLOW; IMPLOSIONS; K SHELL; KEV RANGE; KINETIC ENERGY; KRYPTON; MAGNETOHYDRODYNAMICS; PHOTONS; RAYLEIGH-TAYLOR INSTABILITY; SANDIA NATIONAL LABORATORIES; TEMPERATURE RANGE 0400-1000 K; THREE-DIMENSIONAL CALCULATIONS

Citation Formats

Jennings, C. A., Ampleford, D. J., Lamppa, D. C., Hansen, S. B., Jones, B., Harvey-Thompson, A. J., Jobe, M., Strizic, T., Reneker, J., Rochau, G. A., and Cuneo, M. E. Computational modeling of Krypton gas puffs with tailored mass density profiles on Z. United States: N. p., 2015. Web. doi:10.1063/1.4921154.
Jennings, C. A., Ampleford, D. J., Lamppa, D. C., Hansen, S. B., Jones, B., Harvey-Thompson, A. J., Jobe, M., Strizic, T., Reneker, J., Rochau, G. A., & Cuneo, M. E. Computational modeling of Krypton gas puffs with tailored mass density profiles on Z. United States. doi:10.1063/1.4921154.
Jennings, C. A., Ampleford, D. J., Lamppa, D. C., Hansen, S. B., Jones, B., Harvey-Thompson, A. J., Jobe, M., Strizic, T., Reneker, J., Rochau, G. A., and Cuneo, M. E. 2015. "Computational modeling of Krypton gas puffs with tailored mass density profiles on Z". United States. doi:10.1063/1.4921154.
@article{osti_22410412,
title = {Computational modeling of Krypton gas puffs with tailored mass density profiles on Z},
author = {Jennings, C. A. and Ampleford, D. J. and Lamppa, D. C. and Hansen, S. B. and Jones, B. and Harvey-Thompson, A. J. and Jobe, M. and Strizic, T. and Reneker, J. and Rochau, G. A. and Cuneo, M. E.},
abstractNote = {Large diameter multi-shell gas puffs rapidly imploded by high current (∼20 MA, ∼100 ns) on the Z generator of Sandia National Laboratories are able to produce high-intensity Krypton K-shell emission at ∼13 keV. Efficiently radiating at these high photon energies is a significant challenge which requires the careful design and optimization of the gas distribution. To facilitate this, we hydrodynamically model the gas flow out of the nozzle and then model its implosion using a 3-dimensional resistive, radiative MHD code (GORGON). This approach enables us to iterate between modeling the implosion and gas flow from the nozzle to optimize radiative output from this combined system. Guided by our implosion calculations, we have designed gas profiles that help mitigate disruption from Magneto-Rayleigh–Taylor implosion instabilities, while preserving sufficient kinetic energy to thermalize to the high temperatures required for K-shell emission.},
doi = {10.1063/1.4921154},
journal = {Physics of Plasmas},
number = 5,
volume = 22,
place = {United States},
year = 2015,
month = 5
}
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