title: Effect of internal flow on the photophoresis of a micron-sized liquid droplet.
abstract: Light irradiation can induce the vectorial motion of an aerosol particle. This phenomenon is often explained in terms of inelastic collision between gas molecules and the aerosol particle under a temperature gradient. We considered the photophoresis of a micron-sized liquid droplet in a rarefied gas atmosphere based on the Boltzmann equation for the atmosphere coupled with the Navier-Stokes equation for the droplet. Two features attributable to induced internal flow in the droplet are analyzed: the contribution of homogeneous energy inflow to the motion of the droplet and the nonlinear scaling of the photophoretic velocity depending on the irradiated light intensity.
authors.affiliation: Okayama Institute for Quantum Physics, Okayama 700-0015, Japan.
authors.forename: Takafumi
authors.initials: T
authors.lastname: Iwaki