Three-dimensional modeling of direct-drive cryogenic implosions on OMEGA

The effects of large-scale (with Legendre modes ≲10) laser-imposed nonuniformities in direct-drive cryogenic implosions on the OMEGA Laser System are investigated using three-dimensional hydrodynamic simulations performed using the newly developed code ASTER. Sources of these nonuniformities include an illumination pattern produced by 60 OMEGA laser beams, capsule offsets (∼10–20 μm), and imperfect pointing, power balance, and timing of the beams (with typical σrms∼10 μm, 10%, and 5 ps, respectively). Two implosion designs using 26-kJ triple-picket laser pulses were studied: a nominal design, in which an 874-μm-diameter capsule is illuminated by about the same-diameter beams, and a more hydrodynamically efficient “R75” design using a 900-μm-diameter capsule and beams of 75% of this diameter. Simulations show that nonuniformities caused by capsule offsets and beam imbalance have the largest effect on implosion performance. These nonuniformities lead to significant distortions of implosion cores, resulting ...

[1]  Phillip Colella,et al.  Efficient Solution Algorithms for the Riemann Problem for Real Gases , 1985 .

[2]  G. Kyrala,et al.  Development of a polar direct-drive platform for studying inertial confinement fusion implosion mix on the National Ignition Facilitya) , 2013 .

[3]  Robert L. McCrory,et al.  Indications of strongly flux-limited electron thermal conduction in laser- target experiments , 1975 .

[4]  M J Moran,et al.  Neutron spectrometry--an essential tool for diagnosing implosions at the National Ignition Facility (invited). , 2012, The Review of scientific instruments.

[5]  P. Woodward,et al.  The Piecewise Parabolic Method (PPM) for Gas Dynamical Simulations , 1984 .

[6]  D. Clark,et al.  Three-dimensional hydrodynamics of the deceleration stage in inertial confinement fusion , 2015 .

[7]  Edward I. Moses,et al.  The National Ignition Facility: Ushering in a new age for high energy density science , 2009 .

[8]  J. Meyer-ter-Vehn,et al.  Inertial confinement by spherical implosion , 2004 .

[9]  P. B. Radha,et al.  Triple-picket warm plastic-shell implosions on OMEGA , 2011 .

[10]  S. Skupsky,et al.  Reduction of laser imprinting using polarization smoothing on a solid-state fusion laser , 1999 .

[11]  M. S. Plesset,et al.  On the Stability of Fluid Flows with Spherical Symmetry , 1954 .

[12]  P. B. Radha,et al.  Neutron yield study of direct-drive, low-adiabat cryogenic D2 implosions on OMEGA laser system , 2009 .

[13]  J. Kilkenny,et al.  Mode 1 drive asymmetry in inertial confinement fusion implosions on the National Ignition Facility , 2014 .

[14]  F. J. Marshall,et al.  A framed monochromatic x-ray microscope for ICF (invited) , 1997 .

[15]  G. Taylor.  The instability of liquid surfaces when accelerated in a direction perpendicular to their planes. I , 1950, Proceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences.

[16]  B. Canaud,et al.  Laser Mégajoule irradiation uniformity for direct drive , 2002 .

[17]  J. A. Marozas,et al.  Two-dimensional simulations of the neutron yield in cryogenic deuterium-tritium implosions on OMEGA , 2010 .

[18]  Steven W. Haan,et al.  Three-dimensional HYDRA simulations of National Ignition Facility targets , 2001 .

[19]  Samuel A. Letzring,et al.  Initial performance results of the OMEGA laser system , 1997 .

[20]  P. B. Radha,et al.  Polar-drive implosions on OMEGA and the National Ignition Facilitya) , 2013 .

[21]  J. Kilkenny,et al.  Three-dimensional simulations of National Ignition Facility implosions: Insight into experimental observablesa) , 2015 .

[22]  J. F. Myatt,et al.  Modeling Crossed-Beam Energy Transfer in Implosion Experiments on OMEGA , 2009 .

[23]  Epstein,et al.  Effect of laser illumination nonuniformity on the analysis of time-resolved x-ray measurements in uv spherical transport experiments. , 1987, Physical review. A, General physics.

[24]  David C. Eder,et al.  Radiation hydrodynamics modeling of the highest compression inertial confinement fusion ignition experiment from the National Ignition Campaign , 2015 .

[25]  Thomas J. Murphy,et al.  The effect of turbulent kinetic energy on inferred ion temperature from neutron spectra , 2014 .

[26]  J. D. Kilkenny,et al.  Polar direct drive on the National Ignition Facility , 2004 .

[27]  J. A. Marozas,et al.  Improving the hot-spot pressure and demonstrating ignition hydrodynamic equivalence in cryogenic deuterium–tritium implosions on OMEGAa) , 2014 .

[28]  Robert A. Forties,et al.  In situ characterization of high-intensity laser beams on OMEGA , 2005 .

[29]  S. Skupsky,et al.  Irradiation uniformity for high-compression laser-fusion experiments , 1999 .

[30]  T. C. Sangster,et al.  Laser-beam zooming to mitigate crossed-beam energy losses in direct-drive implosions. , 2013, Physical review letters.

[31]  V N Goncharov,et al.  High-resolution spectroscopy used to measure inertial confinement fusion neutron spectra on Omega (invited). , 2012, The Review of scientific instruments.

[32]  P. B. Radha,et al.  Multidimensional analysis of direct-drive, plastic-shell implosions on OMEGA , 2004 .

[33]  R. Betti,et al.  X-ray continuum as a measure of pressure and fuel–shell mix in compressed isobaric hydrogen implosion cores , 2015 .

[34]  V. Goncharov,et al.  Performance of Direct-Drive Cryogenic Targets on OMEGA , 2007 .

[35]  Yan Xu,et al.  Laser energy deposition and its dynamic uniformity for direct-drive capsules , 2015 .

[36]  T. C. Sangster,et al.  Effects of local defect growth in direct-drive cryogenic implosions on OMEGA , 2013 .

[37]  L. Spitzer,et al.  TRANSPORT PHENOMENA IN A COMPLETELY IONIZED GAS , 1953 .

[38]  R. S. Craxton,et al.  Time-resolved absorption in cryogenic and room-temperature direct-drive implosionsa) , 2008 .

[39]  G. Kyrala,et al.  Designing symmetric polar direct drive implosions on the Omega laser facility , 2014 .

[40]  J. A. Marozas,et al.  Two-dimensional simulations of plastic-shell, direct-drive implosions on OMEGA , 2004 .

[41]  John Kelly,et al.  Crossed-beam energy transfer in direct-drive implosions , 2011 .

[42]  C Sorce,et al.  Shell trajectory measurements from direct-drive implosion experiments. , 2012, The Review of scientific instruments.

[43]  P. B. Radha,et al.  Demonstration of the highest deuterium-tritium areal density using multiple-picket cryogenic designs on OMEGA. , 2010, Physical review letters.

[44]  Jonathan D. Zuegel,et al.  Mitigation of cross-beam energy transfer: Implication of two-state focal zooming on OMEGA , 2013 .

[45]  R. Courant,et al.  Über die partiellen Differenzengleichungen der mathematischen Physik , 1928 .

[46]  Anthony Skjellum,et al.  A High-Performance, Portable Implementation of the MPI Message Passing Interface Standard , 1996, Parallel Comput..

[47]  V. Goncharov,et al.  The effects of target mounts in direct-drive implosions on OMEGA , 2007 .