Characterisation of Downwards Co-Current Gas-Liquid Annular Flows
File(s)
Accepted version
Author(s)
Zadrazil, I
Markides, CN
Matar, OK
Naraigh, LO
Hewitt, GF
Type
Conference Paper
Abstract
The hydrodynamic characteristics of downwards co-current two-phase (gas-liquid) flows inside a
vertical tube (ID = 32 mm) have been investigated experimentally. Advanced optical techniques, namely Laser
Induced Fluorescence and Particle Tracking Velocimetry, were utilised for the characterisation of these flows
over a wide range of gas and liquid superficial velocities (U_G = 0 – 34 m/s and U_L = 0.034 – 0.182 m/s),
corresponding to Reynolds numbers Re_G = 0 – 84,600 and Re_L = 1,230 – 6,130. A flow regime map, which
contains a previously unreported flow regime, is constructed based on the flow observations. The quantitative
analysis of the liquid films allows the generation of film thickness, wave frequency, bubble size, bubble
frequency and velocity profile data. It was found that the different observed flow regimes posses a characteristic
combination of the investigated quantitative parameters. A model, based on modified mixing-length theory, was
used to predict the liquid film velocity profiles and good agreement was found with the experimental results.
vertical tube (ID = 32 mm) have been investigated experimentally. Advanced optical techniques, namely Laser
Induced Fluorescence and Particle Tracking Velocimetry, were utilised for the characterisation of these flows
over a wide range of gas and liquid superficial velocities (U_G = 0 – 34 m/s and U_L = 0.034 – 0.182 m/s),
corresponding to Reynolds numbers Re_G = 0 – 84,600 and Re_L = 1,230 – 6,130. A flow regime map, which
contains a previously unreported flow regime, is constructed based on the flow observations. The quantitative
analysis of the liquid films allows the generation of film thickness, wave frequency, bubble size, bubble
frequency and velocity profile data. It was found that the different observed flow regimes posses a characteristic
combination of the investigated quantitative parameters. A model, based on modified mixing-length theory, was
used to predict the liquid film velocity profiles and good agreement was found with the experimental results.
Date Acceptance
2012-09-24
Citation
THMT-12. Proceedings of the Seventh International Symposium On Turbulence, Heat and Mass Transfer Palermo, Italy, 24-27 September, 2012
Publisher
Begell House
Journal / Book Title
THMT-12. Proceedings of the Seventh International Symposium On Turbulence, Heat and Mass Transfer Palermo, Italy, 24-27 September, 2012
Copyright Statement
©2012 Begell House, Inc.
Sponsor
Engineering & Physical Science Research Council (EPSRC)
Grant Number
EP/K003976/1
Source
Turbulence, Heat and Mass Transfer 7
Subjects
Science & Technology
Technology
Engineering, Mechanical
Engineering
SIZE DISTRIBUTION
2-PHASE FLOW
FILMS
Publication Status
Published
Start Date
2012-09-24
Finish Date
2012-09-27
Coverage Spatial
Palermo, Italy