Comparison among drag coefficient models of single bubbles under high and low Morton number regimes. (8th June 2021)

• Record Type: Journal Article
• Authors: Freitas, Lucas Gusmão; Pereira, Luiz Antonio Alcântara; Lima e Silva, Ana Lúcia Fernandes de
• Is Part Of: Chemical engineering science. Volume 236(2021)
• Publication Date: 2021-06-08
• Subjects: Bubble dynamics -- Drag coefficient -- Aspect ratio; 00-01 -- 99-00; Chemical engineering -- Periodicals; Génie chimique -- Périodiques; Chemical engineering; Periodicals; Electronic journals; 660
• DOI: 10.1016/j.ces.2021.116473
• Languages: English
• ISSNs: 0009-2509

Abstract

Graphical abstract: Highlights: Drag coefficient models comparison. Terminal velocity computation. Bubble dynamics simulations with several forces considered. Evaluation of bubble deformation by aspect ratio prediction. Model drag coefficient proposal for large departures of bubble sphericity. Abstract: Bubble dynamics analysis is highly dependent on drag coefficient computation, and several models have been proposed to compute it. The present study reviewed some of the correlations for the drag coefficient evaluation, and aims to compare the most successfull models available and how they fit the experimental data, spanning over several orders of Morton number regimes ( - 10.6 ⩽ log 10 M ⩽ 0.6 ), including bubbles with different geometrical shapes: spherical, ellipsoidals and cap-like bubbles. The present study categorized the correlations based on their dependency on the aspect ratio. The aspect ratio-dependent models showed great results for E > 0.5, whereas for large departures from sphericity, the independent models fit well the experimental data. To tackle the shortcomings found in these models, a new hybrid correlation was proposed that showed a good compatibility with the experimental results for log 10 M ⩽ - 1.5, 0.1 ⩽ Eo ⩽ 100 and 1 ⩽ Re ⩽ 2000 with a maximum average difference from the experimental values for bubble terminal velocity and aspect ratio within respectively 10% and 15%.