A study on the motion characteristics of particle in shear flow of active nematic fluid between two plates

Abstract

Abstract The motion characteristics of particle in shear flow of active nematic fluid between two plates are investigated numerically. The influence of activity intensity of active nematic fluids on the motion characteristics of particle is focused. The results showed that, when the activity intensity is high, the particle exhibits initially smooth trajectories and ultimately approximate Brownian motion. As the activity intensity increases, both the translational mean square displacement (MSDT) and rotational mean square displacement (MSDR) of the particle increase. The particle exhibits initially super-diffusive behavior and then normal diffusion. The unique vortex lattice mode in the flow plays a role in hindering particle motion, leading to a decrease in MSDT and MSDR. An increase in particle size will lead to a weakening of particle diffusion. In addition, there are topological defects in the active nematic fluid, and the number of topological defects N def in the contractile system is greater than that in the extensible system, while the presence of particle has a smaller impact on N def in the flow.