Ostwald Ripening of Buoyancy-Driven Microbubbles

Yuki Uematsu

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arXiv · 2503.22128

Ostwald Ripening of Buoyancy-Driven Microbubbles

Yuki Uematsu

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Abstract

Microbubble solutions have a wide range of industrial applications, including heat transfer, agriculture, and water treatment. Therefore, understanding and controlling the size variation of bubbles is critical. In this study, we develop a theoretical framework for Ostwald ripening in buoyancy-driven microbubbles by introducing a height-dependent size distribution function. For the first time, we show that the population balance equation in steady state can be interpreted within the Lifshitz-Slezov-Wagner theory when the distribution function is redefined as the density distribution of the buoyancy-induced flux. Notably, in this form of Ostwald ripening, the distribution function approaches a scaled universal distribution, not over time, but as a function of height. We analytically derive the scaled universal distribution and show that the fifth power of the mean radius of the bubbles grows linearly with height.

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Yuki Uematsu. 2025-03-28. Ostwald Ripening of Buoyancy-Driven Microbubbles. https://arxiv.org/abs/2503.22128

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