Imperial College London

Emeritus ProfessorGeoffreyHewitt

Faculty of EngineeringDepartment of Chemical Engineering

Emeritus Professor



+44 (0)20 7594 5562g.hewitt




Mrs Sarah Payne +44 (0)20 7594 5567




507aACE ExtensionSouth Kensington Campus






BibTex format

author = {Zadrazil, I and Markides, CN and Hewitt, GF and Matar, OK},
title = {Structure and Velocity Profiles in Downwards Gas-Liquid Annular Flow},
url = {},

RIS format (EndNote, RefMan)

AB - The downwards co-current gas-liquid annular flows inside a vertically oriented pipe have been experimentally investigated.The measurements and characterisation were performed using advanced optical non-intrusive laser-based techniques, namelyLaser Induced Fluorescence, and Particle Image/Tracking Velocimetry. The investigated conditions were in the range of ReL =306 – 1,532 and ReG = 0 – 84,600. Temporal film thickness time traces were constructed using the Laser Induced Fluorescenceimages. Based on these, the wave frequency was evaluated using direct wave counting approach and power spectral densityanalysis. Additionally, qualitative PIV observations revealed the presence of recirculation zones within a wave front ofdisturbance waves.
AU - Zadrazil,I
AU - Markides,CN
AU - Hewitt,GF
AU - Matar,OK
TI - Structure and Velocity Profiles in Downwards Gas-Liquid Annular Flow
UR -
ER -