Hot-Spot Flow Dynamics and Residual Kinetic Energy in NIF ICF Implosions

ORAL

Abstract

Inertial confinement fusion relies on converting kinetic energy imparted during an implosion into thermal energy of the deuterium-tritium fuel. Non-radial motion in the fusing volume (``hot-spot'') indicates residual kinetic energy and hence inefficient conversion. We present velocities internal to the hot-spot measured by 2D particle velocimetry of x-ray images. These are quantitatively compared to 2D hydrodynamic simulations for several magnitudes of low-mode asymmetric drive. Effects on burn-averaged ion temperatures are shown in observations, simulations and theory. Measurements of burn-averaged electron temperatures appear independent of residual motion and remain several hundred keV below minimum T$_{\mathrm{ion}}$ for all cases of asymmetric drive. This discrepancy will be discussed in terms of fuel velocity-variance artificially increasing apparent ion temperatures. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

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Authors

  • David Schlossberg

    Lawrence Livermore Natl Lab, LLNL, Lawrence Livermore National Laboratory

  • Mark Eckart

    Lawrence Livermore Natl Lab, Lawrence Livermore National Laboratory

  • Gary Grim

    Lawrence Livermore Natl Lab, Lawrence Livermore National Laboratory

  • Edward Hartouni

    Lawrence Livermore Natl Lab, LLNL, Lawrence Livermore National Laboratory

  • Robert Hatarik

    Lawrence Livermore Natl Lab, Lawrence Livermore National Laboratory

  • Alastair Moore

    Lawrence Livermore Natl Lab, LLNL, Lawrence Livermore National Laboratory

  • Prav Patel

    Lawrence Livermore Natl Lab, Lawrence Livermore National Laboratory