Thermophoresis in colloidal suspensions driven by Marangoni forces

Alois Würger (1)

1 CPMOH - Centre de physique moléculaire optique et hertzienne

In a hydrodynamic approach to thermophoretic transport in colloidal suspensions, the solute velocity u and the solvent flow v(r) are derived from Stokes' equation, with slip boundary conditions imposed by thermal Marangoni forces. The resulting fluid velocity field v(r) significantly differs from that induced by an externally driven particle. We find in particular that thermophoresis due to surface forces is insensitive to hydrodynamic interactions. As a consequence, the thermal diffusion coefficient D_{T} of polymer solutions is independent of molecular weight and concentration.

Domaines: Matière Molle [cond-mat.soft]

Alois Würger. Thermophoresis in colloidal suspensions driven by Marangoni forces. Physical Review Letters, 2007, 98, pp.138301. ⟨10.1103/PhysRevLett.98.138301⟩. ⟨hal-00341459⟩