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Conceptual designs of 300-TW and 800-TW pulsed-power accelerators

Stygar, William A.; Fowler, William E.; Gomez, Matthew R.; Harmon, Roger L.; Herrmann, Mark H.; Huber, Dale L.; Hutsel, Brian T.; Bailey, James E.; Jones, Michael J.; Jones, Peter A.; Leckbee, Joshua L.; Lee, James R.; Lewis, Scot A.; Long, Finis W.; Lopez, Mike R.; Lucero, Diego J.; Matzen, M.K.; Mazarakis, Michael G.; McBride, Ryan D.; McKee, George R.; Nakhleh, Charles N.; Owen, Albert C.; Rochau, G.A.; Savage, Mark E.; Schwarz, Jens S.; Sefkow, Adam B.; Sinars, Daniel S.; Stoltzfus, Brian S.; Vesey, Roger A.; Wakeland, P.; Cuneo, M.E.; Flicker, Dawn G.; Focia, Ronald J.

Abstract not provided.

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TYPE Conference YEAR 2013
OSTI

Integration of MHD load models with circuit representations the Z generator

Ampleford, David A.; Savage, Mark E.; Moore, James M.; Jones, Brent M.; McBride, Ryan D.; Bailey, James E.; Jones, Michael J.; Gomez, Matthew R.; Cuneo, M.E.; Nakhleh, Charles N.; 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
OSTIDOI

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

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
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Determination of pressure and density of shocklessly compressed beryllium from x-ray radiography of a magnetically driven cylindrical liner implosion

AIP Conference Proceedings

Lemke, R.W.; Martin, M.R.; McBride, Ryan D.; Davis, Jean-Paul D.; Knudson, Marcus D.; Sinars, Daniel S.; Smith, Ian C.; Savage, Mark E.; Stygar, William A.; Killebrew, K.; Flicker, Dawn G.; Herrmann, Mark H.

We describe a technique for measuring the pressure and density of a metallic solid, shocklessly compressed to multi-megabar pressure, through x-ray radiography of a magnetically driven, cylindrical liner implosion. Shockless compression of the liner produces material states that correspond approximately to the principal compression isentrope (quasi-isentrope). This technique is used to determine the principal quasi-isentrope of solid beryllium to a peak pressure of 2.4 Mbar from x-ray images of a high current (20 MA), fast (∼100 ns) liner implosion. © 2012 American Institute of Physics.

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TYPE Conference YEAR 2012
ScopusOSTI

Solid liner implosions on Z for producing multi-megabar, shockless compressions

Physics of Plasmas

Martin, M.R.; Lemke, Raymond W.; McBride, Ryan D.; Davis, Jean-Paul D.; Dolan, Daniel H.; Knudson, Marcus D.; Cochrane, K.R.; Sinars, Daniel S.; Smith, Ian C.; Savage, Mark E.; Stygar, William A.; Killebrew, K.; Flicker, Dawn G.; Herrmann, Mark H.

Current pulse shaping techniques, originally developed for planar dynamic material experiments on the Z-machine [M. K. Matzen, Phys. Plasmas 12, 055503 (2005)], are adapted to the design of controlled cylindrical liner implosions. By driving these targets with a current pulse shape that prevents shock formation inside the liner, shock heating is avoided along with the corresponding decrease in electrical conductivity ahead of the magnetic diffusion wave penetrating the liner. This results in an imploding liner with a significant amount of its mass in the solid phase and at multi-megabar pressures. Pressures in the solid region of a shaped pulse driven beryllium liner fielded on the Z-machine are inferred to 5.5 Mbar, while simulations suggest implosion velocities greater than 50 kms-1. These solid liner experiments are diagnosed with multi-frame monochromatic x-ray backlighting which is used to infer the material density and pressure. This work has led to a new platform on the Z-machine that can be used to perform off-Hugoniot measurements at higher pressures than are accessible through magnetically driven planar geometries. © 2012 American Institute of Physics.

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TYPE Journal Article YEAR 2012
ScopusOSTI

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

Abstract not provided.

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TYPE Journal Article YEAR 2012
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Penetrating radiography of imploding and stagnating beryllium liners on the Z accelerator

Physical Review Letters

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

Abstract not provided.

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TYPE Journal Article YEAR 2012
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Results 76–100 of 195
Results 76–100 of 195