Three-dimensional Rayleigh-Taylor instability of spherical systems.

A fully three-dimensional Rayleigh-Taylor instability of the pusher-fuel contact surface in a spherically stagnating system is investigated with the use of a new three-dimensional fluid code impact - 3d. Linear growth rates in the simulations agree quite well with analytical values which include spherical-geometry effects. Saturation amplitudes of the exponential growth and free-fall speed following the saturation are found to be, respectively, larger and faster than those of 2D simulations. Nonlinear bubble-spike structures are also studied in detail.