FLOW VISUALIZATION AROUND MESOSCALE SOLID PARTICLE WITHIN A MOVING DROPLET USING MULTI-BODY DISSIPATIVE PARTICLE DYNAMICS
The accuracy of continuum simulations is questionable at micro and nanoscales due to various small-scale effects that are often constrained by limited domain size and computational time. Recently, flow measurement using multi-body dissipative particle dynamics (MDPD) methods in micro and nanoscale devices have been put forward to overcome these challenges. MDPD is a mesoscale particle-based mesh-free method to capture the physics of fluid and its interaction with solid. In this work, MDPD has been used to simulate the dynamics of solid particles in mesoscale fluidic systems. A droplet is kept on a surface with the wettability gradient. Having the droplet to move because of the wettability gradient, a solid particle is put on droplet's trajectory and the droplet's motion causes the solid particle to move along with the droplet. The interaction and dynamics of the droplet with surface and solid particle have been simulated in this study. The velocity field inside a moving droplet around the solid particle is investigated for the first time. The numerical results greatly extend the understanding of the flow field in micro and nanoscales and can be used for various microfluid applications.