Mass transfer during drying of colloidal film beneath a patterned mask that contains a hexagonal array of holes

International Conference on Computer Simulation in Physics and Beyond 2015

物理学;计算机科学

Tarasevich, Yu Yu^1 ; Vodolazskaya, I.V.^1

Astrakhan State University, Russia^1

关键词: Advection-diffusion equation;    Colloidal films;    Colloidal particle;    Drop diameters;    Free surfaces;    Hexagonal arrays;    Hydrophilic surfaces;    Sessile droplet;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/681/1/012033/pdf
DOI  :  10.1088/1742-6596/681/1/012033

学科分类：计算机科学（综合）

来源: IOP

【 摘 要 】

We simulated an experiment in which a thin colloidal sessile droplet is allowed to dry out on a horizontal hydrophilic surface when a mask just above the droplet predominantly allows evaporation from the droplet free surface directly beneath the holes in the mask [Harris D J, Hu H, Conrad J C and Lewis J A 2007 Phys. Rev. Lett. 98 148301]. We considered one particular case when centre-to-centre spacing between the holes is much less than the drop diameter. In our model, advection, diffusion, and sedimentation were taken into account. FlexPDE was utilized to solve an advection-diffusion equation using the finite element method. The simulation demonstrated that the colloidal particles accumulate below the holes as the solvent evaporates. Diffusion can reduce this accumulation.