Segregation and aggregation in a thermally-driven bidisperse suspension

Abstract

We examine the segregation and mixing dynamics of a bidisperse suspension of particles in a fluid subjected to a temperature gradient. Configurations corresponding to varying uniform bottom wall temperatures, as well as various bottom wall temperature profiles, are examined. Measures of spatial segregation and aggregation are discussed and used to analyze the suspension's dynamics. Differences in mass lead to different behavior for light and heavy particles, leading to short time scale separation. The degrees of segregation and aggregation are highest in the configuration which sets up the highest temperature gradients, and therefore the strongest fluid convection currents (that is, the configuration corresponding to a uniform temperature distribution along the bottom wall, with temperature 373 K).