Three-temperature plasma shock solutions with gray radiation diffusion

Journal Article · Tue Apr 19 00:00:00 EDT 2016 · Shock Waves

DOI:https://doi.org/10.1007/s00193-016-0649-9· OSTI ID:1297639

Johnson, Bryan M. ^[1]; Klein, Richard I. ^[2]

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1. Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
2. Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Univ. of California, Berkeley, CA (United States)

Here we discuss the effects of radiation on the structure of shocks in a fully ionized plasma are investigated by solving the steady-state fluid equations for ions, electrons, and radiation. The electrons and ions are assumed to have the same bulk velocity but separate temperatures, and the radiation is modeled with the gray diffusion approximation. Both electron and ion conduction are included, as well as ion viscosity. When the material is optically thin, three-temperature behavior occurs. When the diffusive flux of radiation is important but radiation pressure is not, two-temperature behavior occurs, with the electrons strongly coupled to the radiation. Since the radiation heats the electrons on length scales that are much longer than the electron–ion Coulomb coupling length scale, these solutions resemble radiative shock solutions rather than plasma shock solutions that neglect radiation. When radiation pressure is important, all three components are strongly coupled. Results with constant values for the transport and coupling coefficients are compared to a full numerical simulation with a good match between the two, demonstrating that steady shock solutions constitute a straightforward and comprehensive verification test methodology for multi-physics numerical algorithms.

• Research Organization: Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)
• Sponsoring Organization: USDOE
• Grant/Contract Number: AC52-07NA27344
• OSTI ID: 1297639
• Report Number(s): LLNL-JRNL-685240
• Journal Information: Shock Waves, Journal Name: Shock Waves; ISSN 0938-1287
• Publisher: Springer
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION
plasma shocks
radiative shocks
code verification