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 generalized 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.
- Received 29 January 2019
DOI:https://doi.org/10.1103/PhysRevLett.123.028002
© 2019 American Physical Society
Physics Subject Headings (PhySH)
Synopsis
How Fluids Flow When the Temperature Changes
Published 11 July 2019
Physicists develop a theory to make the seemingly random, thermally driven motion of particles in fluids predictable.
See more in Physics