Nonlinear evolution of multimode Rayleigh--Taylor instability in two and three dimensions

Journal Article · Thu Jun 01 04:00:00 EDT 1995 · Physics of Plasmas

DOI:https://doi.org/10.1063/1.871476· OSTI ID:165305

Shvarts, D ^[1]; Alon, U ^[1]; Ofer, D ^[1]; McCrory, R L; Verdon, C P ^[2]

---

1. Physics Department, Nuclear Research Center Negev, P.O. Box 9001, Beer-Sheva (Israel)
2. Laboratory of Laser Energetics, University of Rochester, 250 East River Rd., Rochester, New York 14623 (United States)

The nonlinear evolution of the Rayleigh--Taylor instability from multimode initial perturbations is studied by two complementary approaches. First, a statistical-mechanics bubble-merger model is presented, that enables determination of the late-time scaling properties based on single-mode and two-bubble interaction physics. The results for Rayleigh--Taylor (RT) and Richtmyer--Meshkov (RM) bubble and spike front penetrations are given, as well as scaling laws for mixing under a time-dependent driving acceleration. The second approach is a modal model, in which nonlinear mode coupling and saturation are included in an equation for effective modes that describe the mixed region. The importance of mode coupling in the generation of large structure that dominates the late stage evolution, and the relative importance of long-wavelength components in the initial perturbation spectra on the late-stage evolution are studied. Finally, multimode RT instability in three dimensions is studied by both full-scale simulations and the modal model. The effect and late-stage memory loss of different aspect ratios in the initial perturbation are demonstrated. {copyright} {ital 1995} {ital American} {ital Institute} {ital of} {ital Physics}.

• OSTI ID: 165305
• Journal Information: Physics of Plasmas, Journal Name: Physics of Plasmas Journal Issue: 6 Vol. 2; ISSN PHPAEN; ISSN 1070-664X
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
70 PLASMA PHYSICS AND FUSION TECHNOLOGY
ABLATION
BUBBLES
ICF DEVICES
IMPLOSIONS
INSTABILITY GROWTH RATES
PLASMA SIMULATION
RAYLEIGH-TAYLOR INSTABILITY
SCALING LAWS
STATISTICAL MECHANICS