Research Repository

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Study of bubbles entrapped into a gas-sheared liquid film (2018)
Journal Article
Hann, D. B., Cherdantsev, A. V., & Azzopardi, B. J. (2018). Study of bubbles entrapped into a gas-sheared liquid film. International Journal of Multiphase Flow, 108, (181-201). doi:10.1016/j.ijmultiphaseflow.2018.07.001. ISSN 0301-9322

The surface of a thick liquid film under strong gas shear is covered by large-scale disturbance waves and small-scale ripples. Disruption of these ripples on top of disturbance waves by the gas stream leads to the creation of droplets that are entrai... Read More

Fluid structure behaviour in gas-oil two-phase flow in a moderately large diameter vertical pipe (2018)
Journal Article
Omar, R. A., Hewakandamby, B. N., Azzi, A., & Azzopardi, B. J. (2018). Fluid structure behaviour in gas-oil two-phase flow in a moderately large diameter vertical pipe. Chemical Engineering Science, 187, doi:10.1016/j.ces.2018.04.075. ISSN 0009-2509

Intermittent flows in vertical pipes occur in many industrial settings including power generation and downstream oil-and gas production. This type of flows include cap bubble, slug and churn flow regimes. These regimes are of interest as downstream p... Read More

Churn flow in high viscosity oils and large diameter columns (2017)
Journal Article
Mohammed, S. K., Hasan, A., Dimitrakis, G., & Azzopardi, B. J. (2018). Churn flow in high viscosity oils and large diameter columns. International Journal of Multiphase Flow, 100, doi:10.1016/j.ijmultiphaseflow.2017.11.018. ISSN 0301-9322

Churn flow is an important intermediate flow regimoccurring in between slug and annular flow patterns in two-phase flow, with profound implications in chemical and petroleum industry. The majority of studies to date in churn flow has been carried out... Read More

Characterisation of an analogue liquid for hydrodynamic studies of gas-ionic liquid flows (2017)
Journal Article
Azzopardi, B. J., Agunlejika, E. O., Zhao, D., Kaji, R., & Hewakandamby, B. N. (2017). Characterisation of an analogue liquid for hydrodynamic studies of gas-ionic liquid flows. Chemical Engineering Journal, 330, doi:10.1016/j.cej.2017.07.090. ISSN 1385-8947

Ionic liquids are liquid salts at low temperatures (normally less than 100°C). They are powerful solvents with very low vapour pressure. They have great potentials in many applications such as gas absorption and chemical synthesis. However, they are... Read More

Numerical modelling of the rise of Taylor bubbles through a change in pipe diameter (2017)
Journal Article
Ambrose, S., Lowndes, I. S., Hargreaves, D., & Azzopardi, B. (2017). Numerical modelling of the rise of Taylor bubbles through a change in pipe diameter. Computers and Fluids, 148, doi:10.1016/j.compfluid.2017.01.023. ISSN 0045-7930

The rise of Taylor bubbles through expansions in vertical pipes is modelled using Computational Fluid Dynamics. The predictions from the models are compared against existing experimental work and show good agreement, both quantitatively and qualitati... Read More

Study of the impacts of droplets deposited from the gas core onto a gas-sheared liquid film (2016)
Journal Article
Cherdantsev, A. V., Hann, D. B., Hewakandamby, B. N., & Azzopardi, B. J. (in press). Study of the impacts of droplets deposited from the gas core onto a gas-sheared liquid film. International Journal of Multiphase Flow, 88, doi:10.1016/j.ijmultiphaseflow.2016.09.015. ISSN 0301-9322

The results of an experimental study on droplet impactions in the flow of a gas-sheared liquid film are presented. In contrast to most similar studies, the impacting droplets were entrained from film surface by the gas stream. The measurements provid... Read More

The control and maintenance of desired flow patterns in bends of different orientations (2016)
Journal Article
Zhao, D., Omar, R., Abdulkadir, M., Abdulkareem, L. A., Azzi, A., Saidj, F., …Azzopardi, B. J. (in press). The control and maintenance of desired flow patterns in bends of different orientations. Flow Measurement and Instrumentation, 53(B), doi:10.1016/j.flowmeasinst.2016.09.003. ISSN 0955-5986

Multiphase flows are common in industrial settings and bends in pipe lines cannot be avoided due to space limitations. Gas-liquid two phase flows could form material discontinuities that could have adverse effect on productivity and the pipe network... Read More

Subatmospheric boiling study of the operation of a horizontal thermosyphon reboiler loop: Instability (2016)
Journal Article
Agunlejika, E. O., Langston, P. A., Azzopardi, B. J., & Hewakandamby, B. N. (in press). Subatmospheric boiling study of the operation of a horizontal thermosyphon reboiler loop: Instability. Applied Thermal Engineering, 109(A), doi:10.1016/j.applthermaleng.2016.08.135. ISSN 1359-4311

Distillation and chemical processing under vacuum is of immense interest to petroleum and chemical industries due to lower energy costs and improved safety. To tap into these benefits, energy efficient reboilers with lower maintenance costs are requi... Read More

Flow instabilities in a horizontal thermosyphon reboiler loop (2016)
Journal Article
Agunlejika, E. O., Langston, P., Azzopardi, B. J., & Hewakandamby, B. N. (2016). Flow instabilities in a horizontal thermosyphon reboiler loop. Experimental Thermal and Fluid Science, 78, doi:10.1016/j.expthermflusci.2016.05.013. ISSN 0894-1777

Thermosyphon systems have been the subject of several studies due to instability issues negating their attractive high heat fluxes, low temperature gradients requirement, reduced weight and simple, pump-less system. There is a dearth of design data f... Read More

Global and local hydrodynamics of bubble columns: effect of gas distributor (2015)
Journal Article
Sharaf, S., Zednikova, M., Ruzicka, M. C., & Azzopardi, B. J. (2016). Global and local hydrodynamics of bubble columns: effect of gas distributor. Chemical Engineering Journal, 288, doi:10.1016/j.cej.2015.11.106. ISSN 1385-8947

Global (level swell) and local (WMS – Wire Mesh Sensor) measurements were made on waters of different purities and air, in a cylindrical laboratory bubble column (2 m tall, 0.127 m dia) using two different gas distributors: a perforated plate (to pro... Read More

Structures in gas–liquid churn flow in a large diameter vertical pipe (2015)
Journal Article
Sharaf, S., van der Meulen, G. P., Agunlejika, E. O., & Azzopardi, B. J. (2016). Structures in gas–liquid churn flow in a large diameter vertical pipe. International Journal of Multiphase Flow, 78, doi:10.1016/j.ijmultiphaseflow.2015.09.005. ISSN 0301-9322

Gas–Liquid two phase co-current flow in a vertical riser with an internal diameter of 127 mm was investigated in the churn flow pattern. This paper presents detailed experimental data obtained using a Wire Mesh Sensor. It shows that the most obvious... Read More

Electrocoalescence of water drop trains in oil under constant and pulsatile electric fields (2015)
Journal Article
Vivacqua, V., Mhatre, S., Ghadiri, M., Abdullah, A., Hassanpour, A., Al-Marri, M., …Kermani, B. (2015). Electrocoalescence of water drop trains in oil under constant and pulsatile electric fields. Chemical Engineering Research and Design, 104, doi:10.1016/j.cherd.2015.10.006. ISSN 0263-8762

This study addresses the effectiveness of constant and pulsed DC fields in promoting coalescence of dispersed water drops in an oil-continuous phase. For this purpose, a train of drops of relatively uniform size is injected into a stream of flowing s... Read More

Comparison of experimental and Computational Fluid Dynamics (CFD) studies of slug flow in a vertical riser (2015)
Journal Article
Abdulkadir, M., Hernandez-Perez, V., Lo, S., Lowndes, I., & Azzopardi, B. J. (in press). Comparison of experimental and Computational Fluid Dynamics (CFD) studies of slug flow in a vertical riser. Experimental Thermal and Fluid Science, 68, doi:10.1016/j.expthermflusci.2015.06.004. ISSN 0894-1777

This paper presents a comparison of the results obtained from experiments and CFD studies of slug flow in a vertical riser. A series of two experimental investigations were carried out on a 6 m vertical pipe with a 0.067 m internal diameter charged w... Read More

Interrogating the effect of an orifice on the upward two-phase gas–liquid flow behavior (2015)
Journal Article
Zeghloul, A., Azzi, A., Saidj, F., Azzopardi, B. J., & Hewakandamby, B. N. (2015). Interrogating the effect of an orifice on the upward two-phase gas–liquid flow behavior. International Journal of Multiphase Flow, 74, doi:10.1016/j.ijmultiphaseflow.2015.04.013. ISSN 0301-9322

Experiments are reported on an air–water mixture flowing through an orifice in a vertical pipe. Time series of cross-sectionally averaged void fractions have been measured at nine axial positions by using a conductance probe technique. A series of si... Read More

Characterization Of oil/ gas flow pattern in vertical pipes using electrical capacitance tomography (2015)
Journal Article
Abdulkareem, L. A., Azzopardi, B. J., Hamid, S. A., & Abdulkahdir, M. (2015). Characterization Of oil/ gas flow pattern in vertical pipes using electrical capacitance tomography. European Journal of Scientific Research, 130(1), ISSN 1450-216X

Electrical Capacitance Tomography provides the opportunity to visualize the contents of a process of many applications such as pipeline and obtain information on the flow configuration. Multiphase flow is an extremely complex field of fluid mechanics... Read More

Electrostatic phase separation: a review (2015)
Journal Article
Mhatre, S., Vivacqua, V., Ghadiri, M., Abdullah, A., Al-Marri, M., Hassanpour, A., …Kermani, B. (2015). Electrostatic phase separation: a review. Chemical Engineering Research and Design, 96, doi:10.1016/j.cherd.2015.02.012. ISSN 0263-8762

The current understanding and developments in the electrostatic phase separation are reviewed. The literature covers predominantly two immiscible and inter-dispersed liquids following the last review on the topic some 15 years. Electrocoalescence kin... Read More

The properties of large bubbles rising in very viscous liquids in vertical columns (2014)
Journal Article
Azzopardi, B. J., Pioli, L., & Abdulkareem, L. (2014). The properties of large bubbles rising in very viscous liquids in vertical columns. International Journal of Multiphase Flow, 67, doi:10.1016/j.ijmultiphaseflow.2014.08.013. ISSN 0301-9322

Very viscous liquids (>100 Pa s) are found in form of heavy oils and polymers in industry as well as in the natural environment (silicatic magma). Little is known of their behaviour as gas bubbles up through them in vertical columns. Using advanced t... Read More

Characteristics of air/water slug flow in an intermediate diameter pipe (2014)
Journal Article
Azzopardi, B. J., Do, H., Azzi, A., & Hernandez Perez, V. (2015). Characteristics of air/water slug flow in an intermediate diameter pipe. Experimental Thermal and Fluid Science, 60, doi:10.1016/j.expthermflusci.2014.08.004. ISSN 0894-1777

Experiments have been carried out in a 67 mm diameter pipe with air and deionised water in which gas superficial velocities between 0.04 and 0.55 m/s were studied. A capacitance technique, employing electrodes mounted on either side of the outside of... Read More