Thermophoresis of spherical and non-spherical particles: a review of theories and experiments

Thermophoresis is an important mechanism of micro-particle transport due to a temperature gradient in the surrounding medium and has found numerous applications, especially in the field of aerosol technology. Extensive studies, both theoretical and experimental, have been done to understand the natu...

Full description

Saved in:
Bibliographic Details
Published in:Advances in colloid and interface science 2002-03, Vol.97 (1), p.255-278
Main Author: Zheng, F.
Format: Article
Language:English
Subjects:
Non-spherical particle
Thermophoresis
Thermophoretic force
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Thermophoresis is an important mechanism of micro-particle transport due to a temperature gradient in the surrounding medium and has found numerous applications, especially in the field of aerosol technology. Extensive studies, both theoretical and experimental, have been done to understand the nature of this phenomenon. However, it is clear that a lot more of work needs to be done before we can predict thermophoresis accurately for any given gas-particle system as well as particle shape and orientation in any flow regime. This paper reviews the existing theories and data in two major categories, for spherical particles and for non-spherical particles, as well as the various techniques in making thermophoresis measurements. The current state of development for thermophoresis studies is that for spheres the theories and experimental data agree with each other fairly well but for non-spherical particles in the transition regime the theories are yet to be developed and experimental data showing the effect of particle shape are much needed in all Knudsen number range. The best techniques of thermophoretic force measurements involve the use of electrodynamic balances to work on single micro-particles and the use of microgravity to minimize the effect of convection. A combination of the above two has not been attempted and should provide the most accurate data.
ISSN:0001-8686
1873-3727
DOI:10.1016/S0001-8686(01)00067-7