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Motion of grains, droplets, and bubbles in fluid-filled nano-pores

Nazar Sushko·Marek Cieplak
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Abstract

Molecular dynamics studies of nono-sized rigid grains, droplets and bubbles in nano-sized pores indicate that the drag force may have a hydrodynamic form if the moving object is dense and small compared to the pore diameter. Otherwise, the behavior is non-hydrodynamic. The terminal speed is insensitive to whether the falling droplet is made of liquid or a solid. The velocity profiles within droplets and bubbles that move in the pore are usually non-parabolic and distinct from those corresponding to individual fluids. The density profiles indicate motional shape distortion of the moving objects.

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Nazar Sushko, Marek Cieplak. 2001-05-05. Motion of grains, droplets, and bubbles in fluid-filled nano-pores. https://doi.org/10.1103/physreve.64.021601

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