Many-Body Dissipative Particle Dynamics Simulations of Ferrofluid Droplet Breakup under External Force-Field*

Our work aims to enhance our understanding of ferrofluid droplet breakup dynamics under external magnetic fields. Ferrofluids are colloidal suspensions of magnetic nanoparticles that can be used in many applications, most notably in soft robotics, where droplets can be externally controlled to perform specific tasks, such as drug transport and delivery. To simulate our system at a mesoscopic length scale, we use many-body dissipative particle dynamics (MDPD). The magnetic nanoparticles are modeled as point particles with a permanent dipole moment that is free to rotate and align with an external field or nearby particles. We perform simulations of the Rayleigh-Plateau instability to understand how the ferrofluid behaves in the presence of a varying field by measuring the characteristic wavelength that drives the breakup. Furthermore, we measure the dynamics of the pinching point to observe the evolution of the breakup regimes, as well as the transport of magnetic nanoparticles and droplet size distributions. With our results, we aim to bridge fundamental research and practical applications, driving technological innovation in soft robotics and biomedical, where external remote control might be required.