Transient laminar natural convection heat transfer from isothermal spheres

H. Jia, George Gogos

Research output: Contribution to journalArticle

15 Citations (Scopus)

Abstract

Transient natural convection over a sphere has been studied numerically for 101 < Gr < 108 and Pr = 0,72. Shortly after the sphere temperature is raised, a vortex of small radial extent appears in the wake of the sphere for very high Gr, which grows radially until the plume formed on the top of the sphere is fully developed. The evolving plume has a mushroom-shaped cap for moderate and high Gr, and in agreement with experiment, presents a temperature peak on the cap's base, an off-axial peak in the middle of the cap, and an axial peak near the cap's leading edge. The mechanism driving the onset of significant convection has been clearly delineated, and the relevant critical Rayleigh numbers have been obtained. The temperature gradient at θ = 90° seems to lead the onset of convection.

Original languageEnglish (US)
Pages (from-to)83-101
Number of pages19
JournalNumerical Heat Transfer; Part A: Applications
Volume29
Issue number1
DOIs
StatePublished - Jan 1 1996

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Natural Convection
Natural convection
caps
free convection
Heat Transfer
heat transfer
Heat transfer
plumes
Convection
convection
Rayleigh number
Wake
leading edges
wakes
Thermal gradients
Vortex
temperature gradients
Vortex flow
vortices
Gradient

ASJC Scopus subject areas

  • Numerical Analysis
  • Condensed Matter Physics

Cite this

Transient laminar natural convection heat transfer from isothermal spheres. / Jia, H.; Gogos, George.

In: Numerical Heat Transfer; Part A: Applications, Vol. 29, No. 1, 01.01.1996, p. 83-101.

Research output: Contribution to journalArticle

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