High Atwood Number Effects in Buoyancy Driven Flows

Abstract

High Atwood number (non-dimensional density difference) effects in buoyancy driven flows are discussed. Buoyancy driven (natural convection) flows may be treated as Boussinesq for small Atwood number, but as Atwood number increases (>0.1, i.e. large temperature differences) the Boussinesq approximation is no longer valid and a distinct “bubble” and “spike” geometry of Rayleigh-Taylor buoyant plumes is formed. Aside from asymmetry in the flow the Atwood number also affects key turbulent mix parameters such as the molecular mix, and heat transfer coefficients. This paper presents recent experimental work being performed in the buoyancy driven mix laboratory at Texas A&M University, using air/helium as mixing components (upto At ∼ 0.5). Corresponding numerical simulations of the experiments performed at Los Alamos is also presented, and future directions for the research discussed.

Meeting Name

American Society of Mechanical Engineers, Fluids Engineering Division (Publication) FED (2006, Chicago, IL)

Department(s)

Mechanical and Aerospace Engineering

Document Type

Article - Conference proceedings

Document Version

Citation

File Type

text

Language(s)

English

Rights

© 2006 American Society of Mechanical Engineers (ASME), All rights reserved.

Publication Date

01 Jan 2006

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