The evolution of the multimode Rayleigh-Taylor instability of nearly incompressible fluids, with density ratio r = 2, is investigated by means of two-dimensional hydrodynamic simulations. The study focuses on the effect of the initial perturbation on the evolution towards turbulent mixing. It is shown that, for sufficiently large times, a self-similar mixing regime occurs, in which typical spatial scales (such as the size of the mixed layer) evolve proportionally to g(t - t0f, where g is the gravity, t the time, and i0 is a characteristic time depending on the initial conditions. A model for the prediction of t0 is then presented, which is in agreement with the simulations. © 1993 IOP Pubilishing Ltd.
Evolution of multimode rayleigh-taylor instability towards self-similar turbulent mixing
Guerrieri, A.
1993-01-01
Abstract
The evolution of the multimode Rayleigh-Taylor instability of nearly incompressible fluids, with density ratio r = 2, is investigated by means of two-dimensional hydrodynamic simulations. The study focuses on the effect of the initial perturbation on the evolution towards turbulent mixing. It is shown that, for sufficiently large times, a self-similar mixing regime occurs, in which typical spatial scales (such as the size of the mixed layer) evolve proportionally to g(t - t0f, where g is the gravity, t the time, and i0 is a characteristic time depending on the initial conditions. A model for the prediction of t0 is then presented, which is in agreement with the simulations. © 1993 IOP Pubilishing Ltd.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.