S. Atzeni et A. Guerrieri, EVOLUTION OF MULTIMODE RAYLEIGH-TAYLOR INSTABILITY TOWARDS SELF-SIMILAR TURBULENT MIXING, Europhysics letters, 22(8), 1993, pp. 603-609
The evolution of the multimode Rayleigh-Taylor instability of nearly i
ncompressible fluids, with density ratio r = 2, is investigated by mea
ns of two-dimensional hydrodynamic simulations. The study focuses on t
he effect of the initial perturbation on the evolution towards turbule
nt mixing. It is shown that, for sufficiently large times, a self-simi
lar mixing regime occurs, in which typical spatial scales (such as the
size of the mixed layer) evolve proportionally to g(t - t0)2, where g
is the gravity, t the time, and t0 is a characteristic time depending
on the initial conditions. A model for the prediction of t0 is then p
resented, which is in agreement with the simulations.