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arXiv · 1901.09840

Thermal forces from a microscopic perspective

Pietro Anzini·Gaia Maria Colombo·Zeno Filiberti·Alberto Parola
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Abstract

Thermal gradients lead to macroscopic fluid motion if a confining surface is present along the gradient. This fundamental nonequilibrium effect, known as thermo-osmosis, is held responsible for particle thermophoresis in colloidal suspensions. A unified approach for thermo-osmosis in liquids and in gases is still lacking. Linear Response Theory is generalised to inhomogeneous systems,leading to an exact microscopic theory for the thermo-osmotic flow showing that the effect originates from two independent physical mechanisms, playing different roles in the gas and liquid phases, reducing to known expressions in the appropriate limits.

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Pietro Anzini, Gaia Maria Colombo, Zeno Filiberti, Alberto Parola. 2019-01-28. Thermal forces from a microscopic perspective. https://doi.org/10.1103/physrevlett.123.028002

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