Design and Performance Analysis of a Jet Self-Priming Microbubble Generator with Annular Air Orifices based on CFD-PBM

Guoqing Li; Juan Zhao; Jiawei Mou; Ruiyan Yu; Weijun Gao; Jinming Jiang

doi:10.6919/ICJE.202506_11(6).0041

Authors

Guoqing Li
Juan Zhao
Jiawei Mou
Ruiyan Yu
Weijun Gao
Jinming Jiang

DOI:

https://doi.org/10.6919/ICJE.202506_11(6).0041

Keywords:

CFD-PBM; Microbubble Generator; Structural Design; Gas-Liquid Two-Phase Flow.

Abstract

Microbubble generators are widely used in industrial production, but single-sided air intake can induce bubble eccentricity and uneven size distribution, limiting their performance. To address this issue, a BH-type jet self-priming microbubble generator was proposed, featuring annular air orifices, arc-shaped flow channels, and a stepped tube structure. Visualization experiments were conducted to obtain key simulation parameters, and a CFD-PBM coupled model incorporating the Luo breakup-coalescence mechanism was established to systematically analyze the effects of structural parameters on bubble size distribution. Simulation results show that annular air orifices prevent bubble eccentricity, arc-shaped flow channels reduce the formation of large bubbles, and bubble size remains stable in the stepped tube (0.63±0.12 mm). The optimal configuration was found to be six air orifices and a 3.5° diffuser angle, achieving a gas-liquid mixing uniformity of 45% and an average bubble size of 730 μm. This study demonstrates that the BH-type microbubble generator effectively reduces bubble size and enhances gas-liquid mixing, providing a scalable solution for flotation separation and chemical reactor optimization.

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