Fig. 4.
Characterization of the mixing performance with different tip anlges of sharp-edges. (a) Schematic of the microchannel with sidewall sharp-edges. The mixing index was characterized at five different positions (positions 1–5, indicated by the dashed white lines in the figure). (b) 15°: Excellent mixing was quickly achieved after position 2. (c) 30°: Acceptable mixing was achieved after position 4. (d) 45°: Incomplete mixing. (e) 60°: A laminar flow pattern was observed even if the piezoelectric transducer was ON. (f) Plots of mixing indices at different positions along the microchannel with different tip angles of sharp-edges.