The Coalescence of Bubbles - a Numerical Study
نویسندگان
چکیده
The dynamics of bubble coalescence is studied using a robust numerical model for a multiphase flow system with interfaces. The effects of liquid viscosity and surface tension on bubble coalescence, for which Reynolds number ranges from 10 to 100 and Bond number ranges from 5 to 50, are investigated. It is shown that the numerical model used in this study can accurately capture the complex topological changes during the coalescence. The predicted behaviour of bubble coalescence is in reasonable agreement with our experimental observation. It is found that with a high Reynolds number (low viscosity) a strong liquid jet formed behind the leading bubble inhibits the approach of the following bubble. Hence coalescence does not occur or is postponed. A lower surface tension results in an earlier coalescence because of severe stretching of the interface.
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