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ISSN Online: 2377-424X

ISBN Print: 0-85295-345-3

International Heat Transfer Conference 10
August, 14-18, 1994, Brighton, UK

BUBBLE SIZE IN BUBBLY FLOW IN DUCTS AND BUBBLE COLUMNS

Get access (open in a dialog) DOI: 10.1615/IHTC10.5670
pages 295-299

Abstract

A basic parameter in two phase gas-liquid flow is the size of the bubbles. From the point of view of calculating exchange of heat or momentum between the phases in two fluid models, or of calculating the interfacial area for mass transfer, the size of the bubbles is as important as the void fraction or hold-up.
Theoretical work has tended to regard bubble size as determined by a balance of surface tension and inertial or other forces. In connection with bubbles columns many empirical expressions for bubble diameter have been proposed but they normally have surface tension as a parameter.
The purpose of the paper is to present recent work which suggest that a new theoretical approach may give better results. A new expression for bubble diameter, based on analogy with the structure of single phase turbulent flows, is shown to be in better agreement with data in the literature for developed pipe flow than any of the earlier equations. Also, in spite of not having any empirically adjustable constants in it, the new equation is comparable in accuracy with the empirical expressions that have been proposed for bubble columns.