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arXiv · 0912.0035

To grate a liquid into tiny droplets by its impact on a hydrophobic micro-grid

P. Brunet·F. Lapierre·F. Zoueshtiagh·V. Thomy·A. Merlen
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Abstract

We report on experiments of drop impacting a hydrophobic micro-grid, of typical spacing a few tens of $\mu$m. Above a threshold in impact speed, liquid emerges to the other side, forming micro-droplets of size about that of the grid holes. We propose a method to produce either a mono-disperse spray or a single tiny droplet of volume as small as a few picoliters corresponding to a volume division of the liquid drop by a factor of up to 10$^5$. We also discuss the discrepancy of the measured thresholds with that predicted by a balance between inertia and capillarity.

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P. Brunet, F. Lapierre, F. Zoueshtiagh, V. Thomy, A. Merlen. 2009-11-30. To grate a liquid into tiny droplets by its impact on a hydrophobic micro-grid. https://doi.org/10.1063/1.3275709

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