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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
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 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
OSTIDOI

Electrothermal instability growth in magnetically driven pulsed power liners

Physics of Plasmas

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

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, 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
OSTIDOI

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
OSTIDOI

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

Fusion Science and Technology

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

Plasma power station with quasi spherical direct drive capsule for fusion yield and inverse diode for driver-target coupling

Fusion Science and Technology

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

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. We report the system configuration and end-toend 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 Conference YEAR 2012
ScopusOSTI

Inverse diode for combination of multiple modules and fusion driver-target standoff

Digest of Technical Papers-IEEE International Pulsed Power Conference

VanDevender, J.P.; Seidel, David B.; Mikkelson, Kenneth A.; Thomas, Rayburn D.; Peyton, B.P.; Harper-Slaboszewicz, V.H.; McBride, Ryan D.; Cuneo, M.E.; Schneider, Larry X.

A newly invented, multi-megampere inverse diode converts the currents in many electron beams to current in a single Magnetically Insulated Transmission Line (MITL) for driving a common load. Electrons are injected through a transparent anode, cross a vacuum gap, and are absorbed in the cathode of the inverse diode. The cathode current returns to the anode through a load and generates electric and magnetic fields in the anode-cathode gap. Counter streaming electron flow is prevented by self-magnetic insulation in most of the inverse diode and by self-electrostatic insulation where the magnetic field is insufficient. Two-dimensional simulations with a 40 MA, 4 MeV, 40 ns electron beam at 3.5 kA/cm 2 current density, 5 degree beam divergence, and up to 60 degree injection angle show 85% of the injected electron beam current is captured and fed into the MITL. Exploratory experiments with a 2.5 MA, 2.8 MeV, 40 ns electron beam at 2 kA/cm 2at injection normal to the anode gave 70+/-10% collection efficiency in an unoptimized inverse diode. The inverse diode appears to have the potential of coupling multiple pulsed power modules into a common load at rates of change of current ∼1.6× 10 15 A/s required for a fusion energy device called the Plasma Power Station with a Quasi Spherical Direct Drive fusion target. © 2011 IEEE.

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TYPE Conference YEAR 2011
ScopusOSTI
Results 151–200 of 387
Results 151–200 of 387