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Integration of MHD load models with circuit representations the Z generator

Ampleford, David J.; Savage, Mark E.; Moore, James K.; Jones, Brent M.; Mcbride, Ryan; Bailey, James E.; Jones, Michael; Gomez, Matthew R.; Cuneo, Michael E.; Nakhleh, Charles; Stygar, William A.

MHD models of imploding loads fielded on the Z accelerator are typically driven by reduced or simplified circuit representations of the generator. The performance of many of the imploding loads is critically dependent on the current and power delivered to them, so may be strongly influenced by the generators response to their implosion. Current losses diagnosed in the transmission lines approaching the load are further known to limit the energy delivery, while exhibiting some load dependence. Through comparing the convolute performance of a wide variety of short pulse Z loads we parameterize a convolute loss resistance applicable between different experiments. We incorporate this, and other current loss terms into a transmission line representation of the Z vacuum section. We then apply this model to study the current delivery to a wide variety of wire array and MagLif style liner loads.

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TYPE SAND Report YEAR 2013
DOIOSTI

Architecture, implementation, and testing of a multiple-shell gas injection system for high current implosions on the Z accelerator

Review of Scientific Instruments

Strizic, Thomas S.; Johnson, Drew; Cunningham, Paul C.; Johns, Owen; Vigil, Marcelino V.; Jones, Brent M.; Ampleford, David J.; Savage, Mark E.; Cuneo, Michael E.; Jones, Michael; Lamppa, Derek C.; Mckenney, John

Tests are ongoing to conduct ~20 MA z-pinch implosions on the Z accelerator at Sandia National Laboratory using Ar, Kr, and D2 gas puffs as the imploding loads. The relatively high cost of operations on a machine of this scale imposes stringent requirements on the functionality, reliability, and safety of gas puff hardware. Here we describe the development of a prototype gas puff system including the multiple-shell nozzles, electromagnetic drivers for each nozzle's valve, a UV pre-ionizer, and an inductive isolator to isolate the ~2.4 MV machine voltage pulse present at the gas load from the necessary electrical and fluid connections made to the puff system from outside the Z vacuum chamber. This paper shows how the assembly couples to the overall Z system and presents data taken to validate the functionality of the overall system.

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TYPE Journal Article YEAR 2013
OSTIDOI

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

Stagnation and disruption of wire array Z-pinch radiation sources on the Z pulsed power generator

IEEE Transactions on Plasma Science

Jones, Brent M.; Ampleford, David J.; Nielsen, D.S.; Coverdale, Christine A.; Jennings, Christopher A.; Cuneo, Michael E.

Magnetic implosions provide extremely intense soft X-ray radiation on the Z accelerator. Shock heating at stagnation provides temperatures that are capable of producing K-shell radiation from stainless steel plasma. Time-gated multicolor X-ray pinhole imaging is used to study stagnation and disruption in fast Z pinches. Magnetohydrodynamic instabilities are observed to grow, following peak X-ray power until the Z-pinch column disrupts well after the main power pulse. © 2006 IEEE.

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TYPE Journal Article YEAR 2011
OSTIScopus

Total x-ray power improvement on recent wire array experiments on the Z machine

Jones, Michael; Ampleford, David J.; Cuneo, Michael E.; Jennings, Christopher A.; Jones, Brent M.; Lopez, Mike R.; Rochau, G.A.; Savage, Mark E.

Recent experiments on the refurbished Z-machine were conducted using large diameter stainless steel arrays which produced x-ray powers of 260 TW. Follow-up experiments were then conducted utilizing tungsten wires with approximately the same total mass with the hypothesis that the total x-ray power would increase. On the large diameter tungsten experiments, the x-ray power averaged over 300 TW and the total x-ray energy was greater than 2MJ. Different analysis techniques for inferring the x-ray power will be described in detail.

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TYPE Conference YEAR 2010
OSTI
Results 201–250 of 319
Results 201–250 of 319