Three-dimensional phase-field lattice-Boltzmann simulations of a rising bubble interacting with obstacles: Shape quantification and parameter dependence

Abstract

Exploring the bubble dynamics in the presence of obstacles can improve understanding of mechanism, design, and operation of multiphase flow. However, large deformation and complex hydrodynamics during the bubble–obstacle interaction pose challenges for shape quantification and parameter dependence. In this work, the bubble–obstacle interaction is investigated by employing a conservative phase-field lattice-Boltzmann model implemented on a parallel platform. Two shape parameters, which are the combination of the bubble geometrical parameters, are defined to characterize the bubble deformation during rising, impacting, and sliding process. The effects of the flow parameters (Reynolds, Eötvös, and Morton numbers) and the obstacle geometry settings (size and layout) are discussed, and a multilinear correlation is established to obtain a thorough evaluation. The difference induced by spatial dimension is further discussed to illustrate the necessity of simulating three-dimensional liquid–gas flow. The results can help decode the intricate bubble dynamics and lay a foundation for developing physically informed models for predicting the bubble–obstacle interaction.