Two-phase momentum flux in pipes and its application to incompressible flow in nozzles

Abstract

The pressure drop produced when a single-phase gas or liquid flows through a nozzle can be reasonably well estimated from inviscid flow theory. A similarly based model, taking the slip with entrained liquid fraction approach, has been developed for two-phase gas—liquid flows. Fundamental to the model is the constraint that the nozzle flow depends on the entry conditions, particularly the momentum flux. At low qualities the tendency was for fractions of the liquid flow to be accelerated with the gas phase to maintain uniform momentum flux across the nozzle flow area. At higher qualities the gas core of the annular flow, along with its associated droplets, was found to contract with negligible interaction with the surrounding liquid film. The model has been compared with data sources and other models available in the literature and shown to perform well.

Keywords

two-phase flow gas-liquid flow nozzles momentum flux two-phase multiplier

Get full access to this article

View all access options for this article.

References

Simpson

H. C

Rooney

D. H.

Gratton

Two-phase flow through gate valves and orifice plates. In Proceedings of International Conference on Physical Modelling of Multi-Phase Flow, Coventry, 19–21 April 1983, paper A2, pp. 25–40.

Whalley

Boiling, Condensation and Gas-Liquid Flow, Oxford Engineering Science Series, 1987 (Clarendon Press, Oxford).

Govan

A. H.

Hewitt

G. F.

Bott

T. R.

Owen

D. G.

An improved CHF modelling code. In Proceedings of 2nd UK National Conference on Heat Transfer, University of Strathclyde, Glasgow, 1988, paper C175/88, pp. 33–48.

Morris

S. D.

A simple model for estimating two-phase momentum flux. In Proceedings of 1st National Conference on Heat Transfer, University of Leeds, 1984, Vol. 2, pp. 773–784.

Massey

B. S.

Mechanics of Fluids, 1975 (Van Nostrand Reinhold, New York).

Chisholm

Two-Phase Flow in Pipelines and Heat Exchangers, 1983 (Goodwin, London).

Premoli

Francesco

Prima

An empirical correlation for evaluating two-phase mixture density under adiabatic conditions. In European Two-Phase Flow Group Meeting, Milan, 1970.

Andeen

G. B.

Griffith

Momentum flux in two-phase flow. J. Heat Transfer, 1968, 90, 211–222.

Hewitt

G. F.

Roberts

D. N.

Studies of two-phase flow patterns in simultaneous flash and X-ray photography. AERE-M2159, Harwell, 1969.

10.

Rose

Some hydrodynamic characteristics of bubbly mixtures flowing vertically upwards in tubes. PhD thesis, Massachusetts Institute of Technology, 1964.

11.

Graham

E. J.

The flow of air-water mixtures through nozzles. NEL Report 308, National Engineering Laboratory, East Kilbride, Scotland, 1967.

12.

McNeil

D. A.

A momentum approach to pressure drop prediction in compressible two-phase flow through contraction/expansion type fittings. In Proceedings of International Conference on Basic Principles and Industrial Applications of Multiphase Flow, Marriott Hotel, London, 24–25 April) 1990.

13.

McNeil

D. A.

Morris

S. D.

A simple explicit method for estimating gas/liquid choked flow conditions in pipeline restrictions. In Proceedings of 2nd UK National Conference on Heat Transfer, University of Strathclyde, Glasgow, 1988, paper C143/88, pp. 1243–1256.

14.

Wan

P. T.

Two-phase flow measurements with flow nozzles. ASME paper HT-58, 1990.

15.

Fairhurst

C. P.

Component pressure loss during two-phase flow. In Proceedings of International Conference on Physical Modelling of Multi-Phase Flow, Coventry, 19–21 April 1983, paper Al, pp. 1–24.