On the Evolution From Micrometer-Scale Inhomogeneity to Global Overheated Structure During the Intense Joule Heating of a z-Pinch Rod

Awe, T. J.; Yu, E. P.; Yates, K. C.; Yelton, W. G.; Bauer, B. S.; Hutchinson, T. M.; Fuelling, S.; Mckenzie, B. B.

doi:10.1109/TPS.2017.2655450

Title: On the Evolution From Micrometer-Scale Inhomogeneity to Global Overheated Structure During the Intense Joule Heating of a z-Pinch Rod

Abstract

Ultrafast optical microscopy of metal z-pinch rods pulsed with megaampere current is contributing new data and critical insight into what provides the fundamental seed for the magneto-Rayleigh-Taylor (MRT) instability. A two-frame near infrared/visible intensified-charge-coupled device gated imager with 2-ns temporal resolution and 3-μm spatial resolution captured emissions from the nonuniformly Joule heated surfaces of ultrasmooth aluminum (Al) rods. Nonuniform surface emissions are consistently first observed from discrete, 10-μm scale, subelectronvolt spots. Aluminum 6061 alloy, with micrometer-scale nonmetallic resistive inclusions, forms several times more spots than 99.999% pure Al 5N; 5-10 ns later, azimuthally stretched elliptical spots and distinct strata (40-100 μm wide by 10 μm tall) are observed on Al 6061, but not on Al 5N. In such overheat strata, aligned parallel to the magnetic field, we find that they are highly effective seeds for MRT instability growth. Our data give credence to the hypothesis that early nonuniform Joule heating, such as the electrothermal instability, may provide the dominant seed for MRT.

Authors:

^[1]; Yu, E. P. ^[1]; Yates, K. C. ^[2]; Yelton, W. G. ^[1]; Bauer, B. S. ^[3]; Hutchinson, T. M. ^[3]; Fuelling, S. ^[3]; Mckenzie, B. B. ^[1]

Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
Univ. of New Mexico, Albuquerque, NM (United States)
Univ. of Nevada, Reno, NV (United States)

Publication Date:: Tue Feb 21 00:00:00 EST 2017

Research Org.:: Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

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

OSTI Identifier:: 1357019

Report Number(s):: SAND2016-12472J
Journal ID: ISSN 0093-3813; 649812; TRN: US1702159

Grant/Contract Number:: AC04-94AL85000

Resource Type:: Accepted Manuscript

Journal Name:: IEEE Transactions on Plasma Science

Additional Journal Information:: Journal Volume: 45; Journal Issue: 4; Journal ID: ISSN 0093-3813

Publisher:: IEEE

Country of Publication:: United States

Language:: English

Subject:: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; electrothermal effects; magnetic fields; optical imaging; plasma pinch; plasma stability

Citation Formats


                    Awe, T. J., Yu, E. P., Yates, K. C., Yelton, W. G., Bauer, B. S., Hutchinson, T. M., Fuelling, S., and Mckenzie, B. B. On the Evolution From Micrometer-Scale Inhomogeneity to Global Overheated Structure During the Intense Joule Heating of a z-Pinch Rod.  United States: N. p., 2017. 
Web.  doi:10.1109/TPS.2017.2655450.

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                    Awe, T. J., Yu, E. P., Yates, K. C., Yelton, W. G., Bauer, B. S., Hutchinson, T. M., Fuelling, S., & Mckenzie, B. B. On the Evolution From Micrometer-Scale Inhomogeneity to Global Overheated Structure During the Intense Joule Heating of a z-Pinch Rod.  United States.  https://doi.org/10.1109/TPS.2017.2655450

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                    Awe, T. J., Yu, E. P., Yates, K. C., Yelton, W. G., Bauer, B. S., Hutchinson, T. M., Fuelling, S., and Mckenzie, B. B. Tue .  
"On the Evolution From Micrometer-Scale Inhomogeneity to Global Overheated Structure During the Intense Joule Heating of a z-Pinch Rod".  United States.  https://doi.org/10.1109/TPS.2017.2655450.  https://www.osti.gov/servlets/purl/1357019.

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@article{osti_1357019,

  title        = {On the Evolution From Micrometer-Scale Inhomogeneity to Global Overheated Structure During the Intense Joule Heating of a z-Pinch Rod},

  author       = {Awe, T. J. and Yu, E. P. and Yates, K. C. and Yelton, W. G. and Bauer, B. S. and Hutchinson, T. M. and Fuelling, S. and Mckenzie, B. B.},

  abstractNote = {Ultrafast optical microscopy of metal z-pinch rods pulsed with megaampere current is contributing new data and critical insight into what provides the fundamental seed for the magneto-Rayleigh-Taylor (MRT) instability. A two-frame near infrared/visible intensified-charge-coupled device gated imager with 2-ns temporal resolution and 3-μm spatial resolution captured emissions from the nonuniformly Joule heated surfaces of ultrasmooth aluminum (Al) rods. Nonuniform surface emissions are consistently first observed from discrete, 10-μm scale, subelectronvolt spots. Aluminum 6061 alloy, with micrometer-scale nonmetallic resistive inclusions, forms several times more spots than 99.999% pure Al 5N; 5-10 ns later, azimuthally stretched elliptical spots and distinct strata (40-100 μm wide by 10 μm tall) are observed on Al 6061, but not on Al 5N. In such overheat strata, aligned parallel to the magnetic field, we find that they are highly effective seeds for MRT instability growth. Our data give credence to the hypothesis that early nonuniform Joule heating, such as the electrothermal instability, may provide the dominant seed for MRT.},

  doi          = {10.1109/TPS.2017.2655450},

  journal      = {IEEE Transactions on Plasma Science},

  number       = 4,

  volume       = 45,

  place        = {United States},

  year         = {Tue Feb 21 00:00:00 EST 2017},

  month        = {Tue Feb 21 00:00:00 EST 2017}

}

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Works referencing / citing this record:

Metastable Fluid Decay During Electric Explosion of Metallic Foils
journal, December 2017

Oreshkin, V. I.; Zhigalin, A. S.; Rousskikh, A. G.
Russian Physics Journal, Vol. 60, Issue 8
DOI: 10.1007/s11182-017-1228-y

The electro-thermal stability of tantalum relative to aluminum and titanium in cylindrical liner ablation experiments at 550 kA
journal, March 2018

Steiner, Adam M.; Campbell, Paul C.; Yager-Elorriaga, David A.
Physics of Plasmas, Vol. 25, Issue 3
DOI: 10.1063/1.5012891

Investigation of surface evolution for stainless steel electrode under pulsed megagauss magnetic field
journal, February 2018

Zou, Wenkang; Dan, Jiakun; Wang, Guilin
Physics of Plasmas, Vol. 25, Issue 2
DOI: 10.1063/1.5016978

Significant change in threshold for plasma formation and evolution with small variation in copper alloys driven by a mega-ampere current pulse
journal, April 2019

Yates, K. C.; Bauer, B. S.; Fuelling, S.
Physics of Plasmas, Vol. 26, Issue 4
DOI: 10.1063/1.5066559

The effect of the metal phase state on the growth of thermal instabilities in an electrically exploding conductor
journal, August 2019

Oreshkin, V. I.; Khishenko, K. V.; Oreshkin, E. V.
Plasma Research Express, Vol. 1, Issue 3
DOI: 10.1088/2516-1067/ab35ab

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Title: On the Evolution From Micrometer-Scale Inhomogeneity to Global Overheated Structure During the Intense Joule Heating of a z-Pinch Rod

Abstract

Citation Formats

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