Ice Particles Trapped by Temperature Gradients at mbar Pressure

Thorben Kelling; Gerhard Wurm; Christoph Dürmann

doi:10.1063/1.3658824

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arXiv · 1111.1068

Ice Particles Trapped by Temperature Gradients at mbar Pressure

Thorben Kelling·Gerhard Wurm·Christoph Dürmann

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Abstract

In laboratory experiments we observe that ice particles (\leq100 \mu m) entrained in a low pressure atmosphere (~1 mbar) get trapped by temperature gradients between three reservoirs at different tempertature. Confining elements are a peltier element at 250 K (bottom), a liquid nitrogen reservoir at 77 K (top) and the surrounding vacuum chamber at 293 K. Particle levitation and trapping is modeled by an interplay of thermophoresis, photophoresis and gravity. A number of ice particles are trapped simultaneously in close spatial distance to each other at least up to minutes and are accessible for further experiments.

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Thorben Kelling, Gerhard Wurm, Christoph Dürmann. 2011-11-04. Ice Particles Trapped by Temperature Gradients at mbar Pressure. https://doi.org/10.1063/1.3658824

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