Surface effects on spinodal decomposition of incompressible binary fluid mixtures

Institute of Industrial Science, University of Tokyo - Meguro-ku, Tokyo 153-8505, Japan

Received: 8 February 2000
Accepted: 16 May 2000

Abstract

We demonstrate the first three-dimensional simulations of bicontinuous spinodal decomposition of incompressible binary fluid mixtures in a confined geometry. We find that after an initial transient the thickness of a wetting layer L grows with time t as by a diffusion process and later as by a hydrodynamic one. We confirm that the hydrodynamic pumping of fluid via bicontinuous tubes plays dominant roles in the late-stage thickening dynamics of a wetting layer. A domain connected to the wetting layer grows faster than in bulk, which is suggestive of the hydrodynamic origin of the fast-mode kinetics found by Wiltzius and Cumming.