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arXiv · 1109.1652

Knudsen gas provides nanobubble stability

James Seddon·Harold Zandvliet·Detlef Lohse
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Abstract

We provide a model for the remarkable stability of surface nanobubbles to bulk dissolution. The key to the solution is that the gas in a nanobubble is of Knudsen type. This leads to the generation of a bulk liquid flow which effectively forces the diffusive gas to remain local. Our model predicts the presence of a vertical water jet immediately above a nanobubble, with an estimated speed of $\sim3.3\,\mathrm{m/s}$, in good agreement with our experimental atomic force microscopy measurement of $\sim2.7\,\mathrm{m/s}$. In addition, our model also predicts an upper bound for the size of nanobubbles, which is consistent with the available experimental data.

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James Seddon, Harold Zandvliet, Detlef Lohse. 2011-09-08. Knudsen gas provides nanobubble stability. https://doi.org/10.1103/physrevlett.107.116101

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