FINITE BANDWIDTH, FINITE AMPLITUDE CONVECTION

Alan C Newell, JA WHITEHEAD JA

Research output: Contribution to journalArticle

1026 Citations (Scopus)

Abstract

It is shown how a continuous finite bandwidth of modes can be readily incorporated into the description of post-critical Rayleigh-Benard convection by the use of slowly varying (in space and time) amplitudes. Previous attempts have used a multimodal discrete analysis. We show that in addition to obtaining results consistent with the discrete mode approach, there is a larger class of stable and realizable solutions. The main feature of these solutions is that the amplitude and wave-number of the motion is that of the most unstable mode almost everywhere, but, depending on external and initial conditions, the roll couplets in different parts of space maye 180//0 out of phase. The resulting discontinuities are smoothed by hyperbolic tangent functions. In addition, it is clear that the mechanism for propagating spatial nonuniformities is diffusive in character.

Original languageEnglish (US)
Pages (from-to)279-303
Number of pages25
JournalJournal of Fluid Mechanics
Volume38
Issue numberpt 2
StatePublished - Sep 3 1969
Externally publishedYes

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convection
Hyperbolic functions
bandwidth
Bandwidth
Rayleigh-Benard convection
tangents
nonuniformity
discontinuity
Convection

ASJC Scopus subject areas

  • Computational Mechanics
  • Mechanics of Materials
  • Physics and Astronomy(all)
  • Condensed Matter Physics

Cite this

FINITE BANDWIDTH, FINITE AMPLITUDE CONVECTION. / Newell, Alan C; WHITEHEAD JA, JA.

In: Journal of Fluid Mechanics, Vol. 38, No. pt 2, 03.09.1969, p. 279-303.

Research output: Contribution to journalArticle

Newell, AC & WHITEHEAD JA, JA 1969, 'FINITE BANDWIDTH, FINITE AMPLITUDE CONVECTION', Journal of Fluid Mechanics, vol. 38, no. pt 2, pp. 279-303.
Newell, Alan C ; WHITEHEAD JA, JA. / FINITE BANDWIDTH, FINITE AMPLITUDE CONVECTION. In: Journal of Fluid Mechanics. 1969 ; Vol. 38, No. pt 2. pp. 279-303.
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