A model for colloidal suspension under magnetohydrodynamic conditions

TL;DR

This paper introduces a comprehensive model explaining how magnetic fields influence nanoparticle suspension behavior, showing that magnetic forces can both promote aggregation or cause floc disruption depending on flow conditions.

Contribution

The model uniquely accounts for magnetic effects on nanoparticle interactions under different flow regimes, aligning well with recent experimental observations.

Findings

Magnetic fields promote aggregation in laminar flows.

Magnetic fields cause floc disruption in turbulent flows.

The model accurately predicts experimental results.

Abstract

We present a comprehensive model to account for the behavior of suspended nanoparticles under magnetohydrodynamic conditions. The Lorentz force not only drags nanoparticle flocs toward the walls reducing the distance between flocs resulting a more negative total pair interaction potential energy, but also produces extra magnetic-induced stresses inside a floc leading to a change of pair interaction distance thus giving rise to a less negative total potential energy. The model explains quite well the recent experimental results showing that magnetic field assists aggregation in laminar or weak turbulent flows, but favors floc disruption in turbulent regime.