Numerical Investigation of Evaporation Induced Self-Assembly of Sub-Micron Particles Suspended in Water

TL;DR

This study numerically investigates how sub-micron particles self-assemble during water evaporation, revealing clustering and pattern formation through coupled CFD-DEM simulations.

Contribution

It introduces a coupled CFD-DEM simulation approach to analyze particle self-assembly during evaporation, considering heat transfer and contact forces.

Findings

Particles form clusters as water evaporates.

Final packing shows patterned structures and specific coordination distributions.

Simulation captures the dynamics of particle clustering during evaporation.

Abstract

Self-assembly of sub-micron particles suspended in a water film is investigated numerically. The liquid medium is allowed to evaporate leaving only the sub-micron particles. A coupled CFD-DEM approach is used for the simulation of fluid-particle interaction. Momentum exchange and heat transfer between particles and fluid and among particles are considered. A history dependent contact model is used to compute the contact force among sub-micron particles. Simulation is done using the open source software package CFDEM which basically comprises of two other open source packages OpenFOAM and LIGGGHTS. OpenFOAM is a widely used solver for CFD related problems. LIGGGHTS, a modification of LAMMPS, is used for DEM simulation of granular materials. The final packing structure of the sub-micron particles is discussed in terms of distribution of coordination number and radial distribution function (RDF). The final packing structure shows that particles form clusters and exhibit a definite pattern as water evaporates away.