ORIGINAL PAPER
Shapes of an Air Taylor Bubble in Stagnant Liquids Influenced by Different Surface Tensions
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Department of Mechanical Engineering, Faculty of Engineering Chulalongkorn University, Bangkok, 10330 Thailand
Online publication date: 2018-03-14
Publication date: 2018-02-01
International Journal of Applied Mechanics and Engineering 2018;23(1):79-90
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ABSTRACT
The aim of this work is to propose an empirical model for predicting shapes of a Taylor bubble, which is a part of slug flows, under different values of the surface tension in stagnant liquids by employing numerical simulations. The k - Ɛ turbulence model was used in the framework of finite volume method for simulating flow fields in a unit of slug flow and also the pressure distribution on a Taylor bubble surface. Assuming that an air pressure distribution inside the Taylor bubble must be uniform, a grid search method was exploited to find an appropriate shape of a Taylor bubble for six values of surface tension. It was found that the shape of a Taylor bubble would be blunter if the surface tension was increased. This was because the surface tension affected the Froude number, controlling the flow around a Taylor bubble. The simulation results were also compared with the Taylor bubble shape, created by the Dumitrescu-and-Taylor model and former studies in order to ensure that they were consistent. Finally, the empirical model was presented from the simulation results.
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