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Electrothermal instability growth in magnetically driven pulsed power liners

Physics of Plasmas

Sinars, Daniel; Yu, Edmund; Herrmann, Mark H.; Cuneo, Michael E.; Slutz, Stephen A.; Smith, Ian C.; Atherton, B.; Knudson, Marcus D.; Nakhleh, Charles

This paper explores the role of electro-thermal instabilities on the dynamics of magnetically accelerated implosion systems. Electro-thermal instabilities result from non-uniform heating due to temperature dependence in the conductivity of a material. Comparatively little is known about these types of instabilities compared to the well known Magneto-Rayleigh-Taylor (MRT) instability. We present simulations that show electrothermal instabilities form immediately after the surface material of a conductor melts and can act as a significant seed to subsequent MRT instability growth. We also present the results of several experiments performed on Sandia National Laboratories Z accelerator to investigate signatures of electrothermal instability growth on well characterized initially solid aluminum and copper rods driven with a 20 MA, 100 ns risetime current pulse. These experiments show excellent agreement with electrothermal instability simulations and exhibit larger instability growth than can be explained by MRT theory alone. © 2012 American Institute of Physics.

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TYPE Journal Article YEAR 2012
OSTIScopus

Pulsed-power driven inertial confinement fusion development at Sandia National Laboratories

Proposed for publication in 5th Special Issue of the IEEE Transactions on Plasma Science Z-Pinch Plasmas.

Cuneo, Michael E.; Mazarakis, Michael G.; Lamppa, Derek C.; Kaye, Ronald J.; Nakhleh, Charles; Bailey, James E.; Hansen, Stephanie B.; Mcbride, Ryan; Herrmann, Mark H.; Lopez, Andrew J.; Peterson, K.J.; Ampleford, David J.; Jones, Michael; Savage, Mark E.; Jennings, Christopher A.; Martin, Matthew R.; Slutz, Stephen A.; Lemke, Raymond W.; Christenson, Peggy J.; Sweeney, Mary A.; Jones, Brent M.; Yu, Edmund; Mcpherson, Leroy A.; Harding, Eric H.; Knapp, P.F.; Gomez, Matthew R.; Awe, Thomas J.; Stygar, William A.; Leeper, Ramon J.; Ruiz, Carlos L.; Chandler, Gordon A.; Mckenney, John; Owen, Albert C.; Mckee, G.R.; Matzen, M.K.; Leifeste, Gordon T.; Atherton, B.; Vesey, Roger A.; Smith, Ian C.; Geissel, Matthias; Rambo, Patrick K.; Sinars, Daniel; Sefkow, Adam B.; Rovang, Dean C.; Rochau, G.A.

Abstract not provided.

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TYPE Journal Article YEAR 2012
OSTIDOI

Penetrating radiography of imploding and stagnating beryllium liners on the Z accelerator

Physical Review Letters

Mcbride, Ryan; Peterson, K.J.; Sefkow, Adam B.; Nakhleh, Charles; Laspe, Amy R.; Lopez, Mike R.; Smith, Ian C.; Atherton, B.; Savage, Mark E.; Stygar, William A.; Slutz, Stephen A.; Rogers, Thomas; Jennings, Christopher A.; Sinars, Daniel; Cuneo, Michael E.; Herrmann, Mark H.; Lemke, Raymond W.; Martin, Matthew R.; Vesey, Roger A.

Abstract not provided.

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TYPE Journal Article YEAR 2012
OSTIDOI

High-gain magnetized inertial fusion

Physical Review Letters

Slutz, Stephen A.; Vesey, Roger A.

Magnetized inertial fusion (MIF) could substantially ease the difficulty of reaching plasma conditions required for significant fusion yields, but it has been widely accepted that the gain is not sufficient for fusion energy. Numerical simulations are presented showing that high-gain MIF is possible in cylindrical liner implosions based on the MagLIF concept [S. A. Slutz et al Phys. Plasmas 17, 056303 (2010)PHPAEN1070-664X10.1063/1.3333505] with the addition of a cryogenic layer of deuterium-tritium (DT). These simulations show that a burn wave propagates radially from the magnetized hot spot into the surrounding much denser cold DT given sufficient hot-spot areal density. For a drive current of 60 MA the simulated gain exceeds 100, which is more than adequate for fusion energy applications. The simulated gain exceeds 1000 for a drive current of 70 MA. © 2012 American Physical Society.

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TYPE Journal Article YEAR 2012
OSTIScopus

Plasma Power Station with Quasi Spherical Direct Drive Capsule for Fusion Yield and Inverse Diode for Driver-Target Coupling

Fusion Science and Technology

Cuneo, Michael E.; Matzen, M.K.; Sinars, Daniel; Slutz, Stephen A.; Herrmann, Mark H.; Vesey, Roger A.; Seidel, David B.; Schneider, Larry X.; Mikkelson, Kenneth A.; Harper-Slaboszewicz, V.; Sefkow, Adam B.

The Meier-Moir economic model for Pulsed Power Driven Inertial Fusion Energy shows at least two approaches for fusion energy at 7 to 8 cents/kw-hr: One with large yield at 0.1 Hz and presented by M. E. Cuneo at ICENES 2011 and one with smaller yield at 3 Hz presented in this paper. Both use very efficient and low cost Linear Transformer Drivers (LTDs) for the pulsed power. Here, we report the system configuration and end-to-end simulation for the latter option, which is called the Plasma Power Station (PPS), and report the first results on the two, least mature, enabling technologies: a magnetically driven Quasi Spherical Direct Drive (QSDD) capsule for the fusion yield and an Inverse Diode for coupling the driver to the target. In addition, we describe the issues and propose to address the issues with a prototype of the PPS on the Saturn accelerator and with experiments on a short pulse modification of the Z accelerator test the validity of simulations showing megajoule thermonuclear yield with DT on a modified Z.

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TYPE Journal Article YEAR 2012
OSTIDOI

Observation of instability growth in a copper Z-pinch target using two-color monochromatic X-ray backlighting

IEEE Transactions on Plasma Science

Sinars, Daniel; Wenger, D.F.; Peterson, K.J.; Slutz, Stephen A.; Herrmann, Mark H.; Yu, Edmund; Cuneo, Michael E.; Smith, Ian C.; Atherton, B.; Porter, John L.

Existing monochromatic X-ray backlighting diagnostics at 1.865 and 6.151 keV have been combined to create a two-color monochromatic X-ray backlighting diagnostic. The use of different photon energies can allow a much broader range of areal densities to be observed in a single experiment. Here, we apply the two-color backlighter to the study of instability growth on the outside edge of an initially solid copper rod target driven by a 100-ns rise-time current pulse with a peak value of 20 MA. The different opacity of Cu at these two photon energies allows a dynamic range of ∼1600x to be surveyed instead of ∼60x (assuming a useful transmission range of 5%-95%). © 2006 IEEE.

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TYPE Journal Article YEAR 2011
OSTIScopus
Results 176–200 of 262
Results 176–200 of 262