Many-body dipole-induced dipole model for electrorheological fluids

TL;DR

This paper introduces a many-body dipole-induced dipole (DID) model for electrorheological fluids that accounts for both multipolar and local-field effects, improving accuracy over traditional point-dipole models.

Contribution

It develops a comprehensive many-body DID model that incorporates both multipolar and local-field effects, surpassing previous models limited to one effect.

Findings

Multipolar interactions can dominate over dipole interactions.

Local-field effects provide significant correction to the model.

The new model enhances the accuracy of ER fluid simulations.

Abstract

Theoretical investigations on electrorheological (ER) fluids usually rely on computer simulations. An initial approach for these studies would be the point-dipole (PD) approximation, which is known to err considerably when the particles approach and finally touch due to many-body and multipolar interactions. Thus various work attempted to go beyond the PD model. Being beyond the PD model, previous attempts have been restricted to either local-field effects only or multipolar effects only, but not both. For instance, we recently proposed a dipole-induced-dipole (DID) model which is shown to be both more accurate than the PD model and easy to use. This work is necessary because the many-body (local-field) effect is included to put forth the many-body DID model. The results show that the multipolar interactions can indeed be dominant over the dipole interaction, while the local-field effect may yield an important correction.