Abstract The morphological and hydrodynamic behavior of bubbles in air–water plumes was studied by employing Particle Tracking Velocimetry (PTV) techniques. Individual bubbles were identified by analyzing the instantaneous high-speed camera images of the plume. The bubble velocities were then obtained by Lagrangian tracking of each bubble, based on its size and location. The nature of bubble coalescence and breakup was also investigated based on the change in the projected area of the parent and daughter bubbles. The effect of the bubble position and the air inflow rate on the bubble properties like diameter, aspect ratio, velocity, number flux, etc., and on the coalescence and breakup behavior was investigated. A novel correlation is proposed to estimate the bubble aspect ratio as a function of bubble Reynolds number and Eotvos number, for a wide range of flow conditions, and is compared with existing correlation from the literature.

中文翻译：

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浮力气泡羽流的形态和流动行为

摘要 采用粒子跟踪测速 (PTV) 技术研究了空气-水羽流中气泡的形态和流体动力学行为。通过分析羽流的瞬时高速摄像机图像来识别单个气泡。然后根据每个气泡的大小和位置，通过对每个气泡进行拉格朗日跟踪来获得气泡速度。还根据母子气泡投影面积的变化研究了气泡合并和破裂的性质。研究了气泡位置和空气流入速率对气泡直径、纵横比、速度、数量通量等特性以及聚结和破碎行为的影响。提出了一种新的相关性来估计气泡纵横比作为气泡雷诺数和 Eotvos 数的函数，