A two-phase flow model of the Rayleigh{endash}Taylor mixing zone

Journal Article · Fri Mar 01 04:00:00 EST 1996 · Physics of Fluids (1994)

DOI:https://doi.org/10.1063/1.868863· OSTI ID:278678

Chen, Y; Glimm, J; Sharp, D H; Zhang, Q ^[1]

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1. The University at Stony Brook, Stony Brook, New York 11794-3600 (United States)

The Rayleigh{endash}Taylor instability of an interface separating fluids of distinct density is driven by an acceleration across the interface. Low order statistical moments of fluctuating fluid quantities characterize the hydrodynamics of the mixing zone. A new model is proposed for the momentum coupling between the two phases. This model is validated against computational data for compressible flows, including flows near the incompressible limit. Our main result is a zero parameter first order closure for ensemble averaged two phase flow equations. We do not, however, fully solve the closure problem, as the equations we derive are missing an (internal) boundary condition along any surface for which either phase goes to zero volume fraction. In this sense, the closure problem is reduced from a volume to a surface condition, rather than being solved completely. We compare two formulations of the statistical moments, one based on two phase flow and the other on turbulence models. These formulations describe different aspects of the mixing process. For the problem considered, the two phase flow moments appear to be preferable, in that they subsume the turbulence moments but not conversely. {copyright} {ital 1996 American Institute of Physics.}

• DOE Contract Number: FG02-90ER25084
• OSTI ID: 278678
• Journal Information: Physics of Fluids (1994), Journal Name: Physics of Fluids (1994) Journal Issue: 3 Vol. 8; ISSN 1070-6631; ISSN PHFLE6
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
BOUNDARY CONDITIONS
FLUID-FLUID INTERFACES
MIXING
MOMENTS METHOD
MULTIPHASE FLOW
RAYLEIGH-TAYLOR INSTABILITY
TURBULENT FLOW