Nonlinear evolution of localized perturbations in the deceleration-phase Rayleigh-Taylor instability of an inertial confinement fusion capsule

The evolution of axially symmetric localized perturbations in the deceleration-phase Rayleigh-Taylor instability of an inertial confinement fusion shell capsule is studied by two-dimensional simulations. Large amplitude divot-like mass perturbations were tracked into the deeply nonlinear regime. Dense fluid spikes penetrating the hot spot as well as light material bubbles rising into the dense shell have been studied, using both a full physics model and a simplified (classical) model neglecting thermal conductivity and fusion reactions. The stabilizing effect of ablation (due to electron thermal conductivity and fusion alpha-particle transport) is found to be more pronounced for spikes than for bubbles. For small width perturbations, bubbles grow faster than spikes, contrary to classical model results.

[1]  O. Landen,et al.  The physics basis for ignition using indirect-drive targets on the National Ignition Facility , 2004 .

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

[3]  S. Atzeni.  REVIEW ARTICLE: The physical basis for numerical fluid simulations in laser fusion , 1987 .

[4]  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.

[5]  Stefano Atzeni,et al.  Converging geometry Rayleigh–Taylor instability and central ignition of inertial confinement fusion targets , 2004 .

[6]  Effects of temporal density variation and convergent geometry on nonlinear bubble evolution in classical Rayleigh-Taylor instability. , 2004, Physical review. E, Statistical, nonlinear, and soft matter physics.

[7]  H. Kull.  Bubble motion in the nonlinear Rayleigh-Taylor instability , 1983 .

[8]  J. Meyer-ter-Vehn,et al.  The physics of inertial fusion - Hydrodynamics, dense plasma physics, beam-plasma interaction , 2004 .

[9]  D. Clark,et al.  Nonlinear Rayleigh-Taylor growth in converging geometry. , 2005, Physical review. E, Statistical, nonlinear, and soft matter physics.

[10]  Qiang Zhang.  Analytical Solutions of Layzer-Type Approach to Unstable Interfacial Fluid Mixing , 1998 .

[11]  Stefano Atzeni,et al.  Mechanism of growth reduction of the deceleration-phase ablative Rayleigh-Taylor instability. , 2003, Physical review. E, Statistical, nonlinear, and soft matter physics.

[12]  D. Del Sarto,et al.  Fluid and kinetic simulation of inertial confinement fusion plasmas , 2005, Comput. Phys. Commun..

[13]  D. Layzer,et al.  On the Instability of Superposed Fluids in a Gravitational Field. , 1955 .

[14]  Kunioki Mima,et al.  Self‐consistent growth rate of the Rayleigh–Taylor instability in an ablatively accelerating plasma , 1985 .

[15]  John Lindl,et al.  Ignition scaling laws and their application to capsule design , 2000 .

[16]  D. Clark,et al.  Acceleration- and deceleration-phase nonlinear Rayleigh-Taylor growth at spherical interfaces. , 2005, Physical review. E, Statistical, nonlinear, and soft matter physics.

[17]  H. Takabe,et al.  Rayleigh–Taylor instability in a spherically stagnating system , 1986 .