Effect of angle optimization on particle inertial focusing with asymmetrically curved channels

This study examines the impact of angle optimization on particle inertial focusing within a fluid flow system through numerical simulations. The investigation employs asymmetrically curved channels characterized by circular curved walls and angled straight walls. Various radii of curvature for the circular arc walls and different angles for the straight walls are selected to achieve optimized channel designs and to analyze particle trajectories in both power-law and Newtonian fluids. The study takes into account several parameters, including the channel width at the baffle (dw), power-law index (n), Reynolds number (Re), and the curvature radius (R) of the curved wall. The findings indicate that an increase in dw results in a shift from single-sided to double-sided focusing within the channel. Furthermore, this transition between the two focusing states can be facilitated by increasing the channel Reynolds number, which leads to a shift from a double-point equilibrium position to a single-point equilibrium position. In the case of shear-thinning fluids, the single-point equilibrium position becomes unstable, resulting in a completely unfocused state as dw increases. In contrast, shear-thickening fluids exhibit two stable equilibrium positions that move away from the channel centerline with an increase in dw. The optimal focusing performance and the minimal particle loss rate are achieved when the curvature radius R is set at 900 μm.