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Prediction of film inversion in two-phase flow in coiled tubes

Published online by Cambridge University Press:  26 April 2006

G. F. Hewitt
Affiliation:
Department of Chemical Engineering and Chemical Technology, Imperial College of Science, Technology and Medicine, London SW7 2BY, UK
S. Jayanti
Affiliation:
Department of Chemical Engineering and Chemical Technology, Imperial College of Science, Technology and Medicine, London SW7 2BY, UK

Abstract

Depending on the flow conditions, the liquid film in annular two-phase flow in coiled tubes may be pushed towards the outer or the inner side by the centrifugal force. It is important to understand the mechanism of this ‘film inversion’ in order to develop a predictive model for the film thickness distribution. In this paper, this phenomenon is studied analytically, and a new criterion, based on the secondary flow in the thin liquid film, is proposed to predict its occurrence. The criterion shows good agreement with available experimental data. It is suggested that the analytical model can readily be extended to predict the distribution of the film thickness and film flow rate in coiled tubes.

Type
Research Article
Copyright
© 1992 Cambridge University Press

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References

Banerjee, S., Rhodes, E. & Scott, D. S. 1967 Film inversion of co-current two-phase flow in helical coils. AIChE J. 13, 189191.Google Scholar
Berthoud, G. & Jayanti, S. 1990 Characterisation of dryout in helical coils. Intl J. Heat Mass Transfer 33, 14511463.Google Scholar
Butterworth, D. 1973 An analysis of film flow for horizontal annular flow and condensation in a horizontal tube. UKAEA Rep. AERE R 75775.Google Scholar
Hewitt, G. F. 1961 Analysis of annular two-phase flow: Application of the Dukler analysis to vertical upward flow in a tube. UKAEA Rep. AERE R 3680.Google Scholar
Hewitt, G. F. 1981 Burnout. In Two-phase Flow and Heat Transfer in the Power and Process Industries (ed. A. E. Berlges, J. G. Collier, J. M. Delhaye, G. F. Hewitt & F. Mayinges), chap. 5. Hemisphere.
Hewitt, G. F. & Hall-Taylor, N. S. 1970 Annular Two-phase Flow. Pergamon.
Ito, H. 1959 Friction factors for turbulent flow in curved pipes. Trans. ASME D: J. Basic Engng 81, 123134.Google Scholar
Jayanti, S. 1990 Contribution to the study of non-axisymmetric flows. Ph.D. thesis, Imperial College, University of London.
Jayanti, S. & Berthoud, G. 1988 Dryout in helical coils. 3rd Intl Topical Meeting on Nuclear Power Plant Thermal Hydraulics and Operations, Nov. 14–17, 1988, Seoul; Paper A2.A-4.Google Scholar
Jayanti, S., Hewitt, G. F. & Kightley, J. R. 1990 Fluid flow in curved ducts. Intl J. Num. Methods Fluids 10, 569589.Google Scholar
Jones, I. P., Kightley, J. R., Thompson, C. P. & Wilkes, N. S. 1985 FLOW3D, a computer code for the prediction of laminar and turbulent flow and heat transfer: Release 1. UKAEA Rep. AERE R 11825.Google Scholar
Kozeki, M. 1973 Film thickness and flow boiling for two-phase annular flow in helically coiled tube. Proc. Intl Meeting on Reactor Heat Transfer, Karlsruhe, Germany, pp. 351372.
Pearce, D. L. 1979 Film waves in horizontal annular flow: space-time correlator experiments. GEGB Rep. CERL/RD/L.N 111/79.Google Scholar
Taitel, Y. & Dukler, A. E. 1976 A model for predicting flow regime transitions in horizontal and near horizontal gas-liquid flow. AIChE J. 22, 4755.Google Scholar
Whalley, P. B. 1980 Air—water two-phase flow in a helically coiled tube. Intl J. Multiphase Flow 6, 345356.Google Scholar