Rayleigh–Taylor instabilities in high-energy density settings on the National Ignition Facility

Abstract

The Rayleigh-Taylor (RT) instability occurs at an interface between two fluids of differing density during an acceleration. These instabilities can occur in very diverse settings, from inertial confinement fusion (ICF) implosions over spatial scales of [Formula: see text] cm (10-1,000 μm) to supernova explosions at spatial scales of [Formula: see text] cm and larger. We describe experiments and techniques for reducing ("stabilizing") RT growth in high-energy density (HED) settings on the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory. Three unique regimes of stabilization are described: () at an ablation front, () behind a radiative shock, and () due to material strength. For comparison, we also show results from nonstabilized "classical" RT instability evolution in HED regimes on the NIF. Examples from experiments on the NIF in each regime are given. These phenomena also occur in several astrophysical scenarios and planetary science [Drake R (2005) 47:B419-B440; Dahl TW, Stevenson DJ (2010) 295:177-186].

Inertial dynamics of an interface with interfacial mass flux: Stability and flow fields’ structure, inertial stabilization mechanism, degeneracy of Landau’s solution, effect of energy fluctuations, and chemistry-induced instabilities

“…Non-equilibrium transport, interfaces and mixing are omnipresent in nature and technology at astrophysical and at molecular scales, and in high and low energy density regimes [1]. Fluid instabilities and interfacial mixing in supernovae and in inertial confinement fusion, particle-field interactions in magnetic fusion and in imploding Z-pinches, downdrafts in stellar interior and in planetary magnetoconvection, coronal mass ejections in the Solar flares and plasma instabilities in the Earth ionosphere, plasma thrusters and nano-fabrication -are examples of processes governed by non-equilibrium interfacial dynamics [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19]. The realistic environments are often characterized by sharply and rapidly changing flow fields and by small effects of dissipation and diffusion resulting in the formation of discontinuities (referred to as fronts or as interfaces) between the flow non-uniformities (phases) at macroscopic (continuous) scales [11].…”

Interfaces and mixing: Nonequilibrium transport across the scales

“…This issue reports significant successes that have been achieved recently in understanding interfaces, mixing, and nonequilibrium dynamics based on theoretical analysis, large-scale numerical simulations, laboratory experiments, and technology development (20)(21)(22)(23)(24)(25)(26)(27)(28)(29)(30)(31)(32)(33)(34). These include theoretical approaches for handling complex multiscale, nonlocal, and statistically unsteady dynamics and boundary value problems; developments of efficient Eulerian and Lagrangian methods of large-scale numerical modeling; advancements in laboratory experiments in low-and high-energy density regimes; and possibilities for dramatic improvements in precision, accuracy, dynamic range, reproducibility, and data acquisition rate with the use of modern technologies (20)(21)(22)(23)(24)(25)(26)(27)(28)(29)(30)(31)(32)(33)(34).…”

“…These works represent frontier research in interaction of molecules and chemical reactions, interfacial dynamics and nonequilibrium processes, fluid turbulence and turbulent mixing, supernovas and nuclear synthesis, formation of fluid phases at molecular scales, first-principlesbased reaction kinetics, ion transport of nanoscales, electric and magnetic fields structures, dynamics of high-energy density plasmas, subdiffusive and superdiffusive transport, formation of vortices in geophysical flows, diffusiophoresis of charged particles, and electron transport in macromolecules. They motivate the discussions of rigorous mathematical problems, theoretical approaches, and state-of-the-art numerical simulations along with advanced experimental methods and technological applications (20)(21)(22)(23)(24)(25)(26)(27)(28)(29)(30)(31)(32).…”

“…The contributions in this issue include 6 perspective papers and 7 research papers (20)(21)(22)(23)(24)(25)(26)(27)(28)(29)(30)(31)(32). They are ordered from perspective to research papers, from macroscopic to microscopic scales, and from fundamentals to applications.…”

“…The research paper by Remington et al (27) reviews experiments on Rayleigh-Taylor instabilities in high-energy density settings and explores the properties of matter at extreme conditions. The experiments report observations of a more ordered character in Rayleigh-Taylor dynamics in 3 regimes-at ablation fronts, behind radiative shocks, and due to material strength.…”