| 초록 |
The size stratification in vertical drying of bidisperse colloidal mixtures is investigated using the implicit-solvent Langevin dynamics (LD) simulation and the explicit-solvent lattice Boltzmann (LB) method. The simulations are executed in a wide range of Peclet number (Pe) of 1−4000. At the low size ratio of 2, only mild stratification was observed in both simulation methods, rather than distinctly stratified thick ‘small-on-top’ or ‘large-on-top’ layers. The results of the LD simulations show the stratification patterns of ‘small-on-top’ or mixed state, while the LB results present ‘large-on-top’ or mixed state, according to the variation of Pe. Our results show that, under moderate Pe conditions, the explicit solvent plays a role by lowering collective diffusion – which induces a steep concentration gradient of small particles in the packed region of particles near the air-solvent interface, thereby forming distinguishable stratification patterns between implicit and explicit solvent models. |
