Nucleation and Growth of Tightly Packed Droplets in Fluids

Abstract

Experiments of phase separation have been performed in a density-matched liquid mixture (partially deuterated cyclohexane-methanol at 1.4% below critical concentration) and in a pure fluid (${\mathrm{SF}}_6$ at 3.6% above critical density). The usual strong gravity-induced flows that accompany phase separation in pure fluids are suppressed by performing experiments under reduced gravity. Experiments under microgravity are compared with experiments on Earth. Phase separation under reduced gravity is characterized by a pattern of tightly packed droplets of the minority phase whose growth can be expressed over more than 7 decades in time by a single reduced power law with exponent ⅓.