Computational fluid dynamics modelling of air entrainment for a plunging jet
File(s)
Accepted version
Author(s)
Salehi, Fatemeh
Ajdehak, Esmaeil
Hardalupas, Ioannis
Type
Journal Article
Abstract
This study focuses on computational fluid dynamics (CFD) modelling of the air entrainment phenomena in water columns which are commonly used in processing plants. The CFD model is first validated against experimental data. Then, a comprehensive set of CFD simulations are conducted to understand the effect of inlet jet velocity, nozzle diameter, tank diameter, and
tank height on the bubble formation. Three main patterns are identified: dispersed bubbles, medium air pockets (MAP) and large air pockets (LAP). For the dispersed bubble case, the initially formed air pockets break into smaller bubbles and hence the water level rises linearly. For the MAP case, the size of the air pockets remains larger than for the dispersed bubble case,
though, with time they burst at the surface. Finally, for the LAP case, the inkling jet interacts violently with the wall and hence large air pockets are trapped within the column, causing the overflow of the fluid. The flows are further analysed using non-dimensionless Reynolds and Froude numbers, providing an acceptable range of operating parameters that ensure the fluid
does not overflow.
tank height on the bubble formation. Three main patterns are identified: dispersed bubbles, medium air pockets (MAP) and large air pockets (LAP). For the dispersed bubble case, the initially formed air pockets break into smaller bubbles and hence the water level rises linearly. For the MAP case, the size of the air pockets remains larger than for the dispersed bubble case,
though, with time they burst at the surface. Finally, for the LAP case, the inkling jet interacts violently with the wall and hence large air pockets are trapped within the column, causing the overflow of the fluid. The flows are further analysed using non-dimensionless Reynolds and Froude numbers, providing an acceptable range of operating parameters that ensure the fluid
does not overflow.
Date Acceptance
2021-12-19
Citation
Chemical Engineering Research and Design, 179, pp.319-330
ISSN
0263-8762
Publisher
Elsevier
Start Page
319
End Page
330
Journal / Book Title
Chemical Engineering Research and Design
Volume
179
Identifier
https://www.sciencedirect.com/science/article/pii/S0263876222000326?via%3Dihub
Subjects
Strategic, Defence & Security Studies
Chemical Engineering
0904 Chemical Engineering
0914 Resources Engineering and Extractive Metallurgy
0102 Applied Mathematics
0911 Maritime Engineering
Publication Status
Published