Onedimensional radiationhydrodynamic scaling studies of imploding spherical plasma liners
Abstract
Onedimensional radiationhydrodynamic simulations are performed to develop insight into the scaling of stagnation pressure with initial conditions of an imploding spherical plasma shell or ''liner.'' Simulations reveal the evolution of highMachnumber (M), annular, spherical plasma flows during convergence, stagnation, shock formation, and disassembly, and indicate that cm and {mu}sscale plasmas with peak pressures near 1 Mbar can be generated by liners with initial kinetic energy of several hundred kilojoules. It is shown that radiation transport and thermal conduction must be included to avoid nonphysical plasma temperatures at the origin which artificially limit liner convergence and, thus, the peak stagnation pressure. Scalings of the stagnated plasma lifetime ({tau}{sub stag}) and average stagnation pressure (P{sub stag}, the pressure at the origin, averaged over {tau}{sub stag}) are determined by evaluating a wide range of liner initial conditions. For highM flows, {tau}{sub stag} {approx} {Delta}R/v{sub 0}, where {Delta}R and v{sub 0} are the initial liner thickness and velocity, respectively. Furthermore, for argon liners, P{sub stag} scales approximately as v{sub 0}{sup 15/4} over a wide range of initial densities (n{sub 0}) and as n{sub 0}{sup 1/2} over a wide range of v{sub 0}. The approximate scaling P{sub stag} {approx} M{sup 3/2} is also found formore »
 Authors:
 Physics Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)
 Propulsion Research Center, Technology Hall S226, University of Alabama in Huntsville, Huntsville, Alabama 35899 (United States)
 Publication Date:
 OSTI Identifier:
 22046890
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physics of Plasmas; Journal Volume: 18; Journal Issue: 7; Other Information: (c) 2011 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; APPROXIMATIONS; ARGON; ELECTRON TEMPERATURE; ION TEMPERATURE; MACH NUMBER; ONEDIMENSIONAL CALCULATIONS; PLASMA; PLASMA DENSITY; PLASMA JETS; PLASMA PRESSURE; PLASMA PRODUCTION; PLASMA SIMULATION; RADIANT HEAT TRANSFER; RADIATION TRANSPORT; SHOCK WAVES; SPHERICAL CONFIGURATION; THERMAL CONDUCTION
Citation Formats
Awe, T. J., Adams, C. S., Davis, J. S., Hanna, D. S., Hsu, S. C., and Cassibry, J. T.. Onedimensional radiationhydrodynamic scaling studies of imploding spherical plasma liners. United States: N. p., 2011.
Web. doi:10.1063/1.3610374.
Awe, T. J., Adams, C. S., Davis, J. S., Hanna, D. S., Hsu, S. C., & Cassibry, J. T.. Onedimensional radiationhydrodynamic scaling studies of imploding spherical plasma liners. United States. doi:10.1063/1.3610374.
Awe, T. J., Adams, C. S., Davis, J. S., Hanna, D. S., Hsu, S. C., and Cassibry, J. T.. 2011.
"Onedimensional radiationhydrodynamic scaling studies of imploding spherical plasma liners". United States.
doi:10.1063/1.3610374.
@article{osti_22046890,
title = {Onedimensional radiationhydrodynamic scaling studies of imploding spherical plasma liners},
author = {Awe, T. J. and Adams, C. S. and Davis, J. S. and Hanna, D. S. and Hsu, S. C. and Cassibry, J. T.},
abstractNote = {Onedimensional radiationhydrodynamic simulations are performed to develop insight into the scaling of stagnation pressure with initial conditions of an imploding spherical plasma shell or ''liner.'' Simulations reveal the evolution of highMachnumber (M), annular, spherical plasma flows during convergence, stagnation, shock formation, and disassembly, and indicate that cm and {mu}sscale plasmas with peak pressures near 1 Mbar can be generated by liners with initial kinetic energy of several hundred kilojoules. It is shown that radiation transport and thermal conduction must be included to avoid nonphysical plasma temperatures at the origin which artificially limit liner convergence and, thus, the peak stagnation pressure. Scalings of the stagnated plasma lifetime ({tau}{sub stag}) and average stagnation pressure (P{sub stag}, the pressure at the origin, averaged over {tau}{sub stag}) are determined by evaluating a wide range of liner initial conditions. For highM flows, {tau}{sub stag} {approx} {Delta}R/v{sub 0}, where {Delta}R and v{sub 0} are the initial liner thickness and velocity, respectively. Furthermore, for argon liners, P{sub stag} scales approximately as v{sub 0}{sup 15/4} over a wide range of initial densities (n{sub 0}) and as n{sub 0}{sup 1/2} over a wide range of v{sub 0}. The approximate scaling P{sub stag} {approx} M{sup 3/2} is also found for a wide range of linerplasma initial conditions.},
doi = {10.1063/1.3610374},
journal = {Physics of Plasmas},
number = 7,
volume = 18,
place = {United States},
year = 2011,
month = 7
}

This work extends the onedimensional radiationhydrodynamic imploding spherical argon plasma liner simulations of Awe et al.[Phys. Plasmas 18, 072705 (2011)] by using a detailed tabular equationofstate (EOS) model, whereas Awe et al. used a polytropic EOS model. Results using the tabular EOS model give lower stagnation pressures by a factor of 3.98.6 and lower peak ion temperatures compared to the polytropic EOS results. Both local thermodynamic equilibrium (LTE) and nonLTE EOS models were used in this work, giving similar results on stagnation pressure. The lower stagnation pressures using a tabular EOS model are attributed to a reduction in the liner'smore »

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