NONLINEAR SATURATION OF THE RAYLEIGH-TAYLOR INSTABILITY

A detailed numerical simulation of the nonlinear state of the Rayleigh -Taylor instability has been carried out. There are three distinct pha ses of evolution where it is governed by the (i) linear effects, (ii) effects arising from the conventional nonlinear terms and (iii) subtle nonlinear effects arising through the coupling terms. During the thir d phase of evolution, there is a self-consistent generation of shear f low which saturates the Rayleigh-Taylor instability even in situations (with periodic boundaries) where, in principle, an infinite amount of gravitational energy can be tapped. The Galerkin approximation is pre sented to provide an understanding of our numerical findings. Last, th ere is an attempt to provide a comprehensive understanding of the nonl inear state of the Rayleigh-Taylor instability by comparing and contra sting this work with earlier studies. (C) 1997 American Institute of P hysics.