Vol. 38, issue 06, article # 5

Abstract:

Thermophoresis of aerosols traditionally has been studied both theoretically and experimentally for spherical or, more generally, compact isometric particles. This paper compares the theory of thermophoretic motion of fractal-like particles developed by the authors with experimental data for carbon aggregates obtained in the gas phase under the DLCA formation scenario. It is shown that the theoretical results for the thermophoretic velocity qualitatively and quantitatively agree well with experiment. Possible limitations of the proposed theory and fundamental issues related to the estimation of the determining structural and thermophysical parameters for fractal-like aggregates are discussed. The results can be useful for the physics of atmospheric aerosols in modeling the processes of carbonaceous particles motion with fractal properties.

Keywords:

thermophoresis, thermophoretic velocity, fractal-like aggregate, DLCA scenario, effective thermal conductivity

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