Calculation of the Equilibrium Evolution of the ZaP Flow $Z$ -Pinch Using a Four-Chord Interferometer

Knecht, Sean D.; Golingo, Raymond P.; Nelson, Brian A.; Shumlak, Uri

doi:10.1109/TPS.2015.2431973

Title: Calculation of the Equilibrium Evolution of the ZaP Flow $$Z$$ -Pinch Using a Four-Chord Interferometer

Abstract

For this study, a four-chord interferometer and measurements from an array of surface-mounted magnetic probes were used in conjunction with equations of radial heat conduction and radial force balance to calculate the equilibrium evolution of a pinch plasma in the ZaP Flow Z-Pinch. A multiple shooting method was used to solve the nonlinear coupled differential equation system, with Ohmic heating and bremsstrahlung radiation as sources and sinks, respectively. Data from a single ZaP pulse are reported including profiles of magnetic field and temperature and their evolution. Profiles are dominated by high thermal conductivity near the axis which quickly decreases with radius. This is due to the plasma being weakly magnetized near the axis which increases thermal conductivity and flattens the temperature profile, but strongly magnetized near the characteristic radius, significantly reducing thermal conductivity and resulting in a large temperature gradient. The equilibrium evolution indicates that plasmas in ZaP heat and compress with increasing current as a result of magnetic compression during the quiescent period.

Authors:

Knecht, Sean D. ^[1]; Golingo, Raymond P. ^[2]; Nelson, Brian A. ^[2];

^[2]

Univ. of Washington, Seattle, WA (United States); Pennsylvania State Univ., University Park, PA (United States). Applied Research Lab.
Univ. of Washington, Seattle, WA (United States). Aerospace and Energetics Research Program

Publication Date:: Mon May 25 00:00:00 EDT 2015

Research Org.:: Univ. of Washington, Seattle, WA (United States)

Sponsoring Org.:: USDOE National Nuclear Security Administration (NNSA)

OSTI Identifier:: 1465209

Grant/Contract Number:: NA0001860

Resource Type:: Accepted Manuscript

Journal Name:: IEEE Transactions on Plasma Science

Additional Journal Information:: Journal Volume: 43; Journal Issue: 8; Journal ID: ISSN 0093-3813

Publisher:: IEEE

Country of Publication:: United States

Language:: English

Subject:: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; 46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; equilibrium evolution; interferometry; pinch oscillation; plasma heating; Z-pinch; plasmas; measurement by laser beam; laser beams; conductors; probes; density measurements

Citation Formats


                    Knecht, Sean D., Golingo, Raymond P., Nelson, Brian A., and Shumlak, Uri. Calculation of the Equilibrium Evolution of the ZaP Flow $Z$ -Pinch Using a Four-Chord Interferometer.  United States: N. p., 2015. 
Web.  doi:10.1109/TPS.2015.2431973.

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                    Knecht, Sean D., Golingo, Raymond P., Nelson, Brian A., & Shumlak, Uri. Calculation of the Equilibrium Evolution of the ZaP Flow $Z$ -Pinch Using a Four-Chord Interferometer.  United States.  https://doi.org/10.1109/TPS.2015.2431973

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                    Knecht, Sean D., Golingo, Raymond P., Nelson, Brian A., and Shumlak, Uri. Mon .  
"Calculation of the Equilibrium Evolution of the ZaP Flow $Z$ -Pinch Using a Four-Chord Interferometer".  United States.  https://doi.org/10.1109/TPS.2015.2431973.  https://www.osti.gov/servlets/purl/1465209.

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@article{osti_1465209,

  title        = {Calculation of the Equilibrium Evolution of the ZaP Flow $Z$ -Pinch Using a Four-Chord Interferometer},

  author       = {Knecht, Sean D. and Golingo, Raymond P. and Nelson, Brian A. and Shumlak, Uri},

  abstractNote = {For this study, a four-chord interferometer and measurements from an array of surface-mounted magnetic probes were used in conjunction with equations of radial heat conduction and radial force balance to calculate the equilibrium evolution of a pinch plasma in the ZaP Flow Z-Pinch. A multiple shooting method was used to solve the nonlinear coupled differential equation system, with Ohmic heating and bremsstrahlung radiation as sources and sinks, respectively. Data from a single ZaP pulse are reported including profiles of magnetic field and temperature and their evolution. Profiles are dominated by high thermal conductivity near the axis which quickly decreases with radius. This is due to the plasma being weakly magnetized near the axis which increases thermal conductivity and flattens the temperature profile, but strongly magnetized near the characteristic radius, significantly reducing thermal conductivity and resulting in a large temperature gradient. The equilibrium evolution indicates that plasmas in ZaP heat and compress with increasing current as a result of magnetic compression during the quiescent period.},

  doi          = {10.1109/TPS.2015.2431973},

  journal      = {IEEE Transactions on Plasma Science},

  number       = 8,

  volume       = 43,

  place        = {United States},

  year         = {Mon May 25 00:00:00 EDT 2015},

  month        = {Mon May 25 00:00:00 EDT 2015}

}

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Works referencing / citing this record:

Drift-ideal magnetohydrodynamic simulations of m = 0 modes in Z-pinch plasmas
journal, July 2019

Angus, J. R.; Dorf, M.; Geyko, V. I.
Physics of Plasmas, Vol. 26, Issue 7
DOI: 10.1063/1.5093625

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Title: Calculation of the Equilibrium Evolution of the ZaP Flow $$Z$$ -Pinch Using a Four-Chord Interferometer

Abstract

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