Dimensionless three-dimensional universal phase and lift force diagrams of a microbubble (or pendant drop) in static liquid on a solid surface (or orifice) are presented in this work. Microbubble dynamics has been found to play a vital role in mass, momentum, energy, and concentration transfer rates in contemporary micro- and nanosciences and technologies. In this study, dimensionless phase and force diagrams are introduced by utilizing the analytical solutions of the microbubble shape reported in the literature. It shows that phase and force diagrams can be universally specified by two dimensionless independent parameters, Bond number, and contact angle (or base radius). Based on the presence of an inflection point or neck on the microbubble surface, each diagram exhibits three regions. Growth, detachment, and entrapment of a microbubble can be described by path lines in three regions. The corresponding universal total lift forces include hydrostatic buoyancy, difference in gas, and hydrostatic pressures at the base, capillary pressure, as well as surface tension induced by the variation of circumference, which has not been treated in the literature so far. In the absence of viscous stress and Marangoni force, the total lift force equals surface tension induced by the variation of circumference. The latter can be an attaching or lifting force, depending on whether the state in the distinct regions and contact angle is less than or greater than a critical angle. The critical angle, which is slightly less than the inclination angle at the inflection point, is decreased with increasing Bond number.
Universal dimensionless three-dimensional universal lift force diagrams for a microbubble (or pendant drop) in a static liquid on a solid surface (or orifice) are presented in this work. Studying microbubble dynamics is important due to its controlling mass, momentum, energy and concentration transfer rates in many micro- and nano-sciences and technologies. In this study, dimensionless force diagrams are introduced by applying the solutions for microbubble shape for small Bond number in literature. A parametric study reveals that two dimensionless independent parameters, Bond number and contact angle (or base radius), are required to specify force diagrams. Each diagram can be divided into three regions, depending on if the microbubble surface contains the inflection or neck point. The total life force includes hydrostatic buoyancy, difference in gas and hydrostatic pressures at the base, capillary pressure, as well as surface tension induced by the variation of circumference which has not been treated in literature. In the absence of viscous stress, the total lift force equals surface tension induced by the variation of circumference.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.