FIG. 9.

Mixing efficiency determination of the merged droplet in a diverging channel using the RMI method. Methylene blue and sunset yellow are used as dispersed phases and silicone oil as a continuous phase. The continuous phase flow rate is 10 $\mu \mathrm{l}/\min$ and the dispersed phase flow rate is 2 $\mu \mathrm{l}/\min$. (a)–(i) Sequence of images shows merging of droplets, and (j) depicts variations of the mixing efficiency of a fused droplet against time. The duration of species homogenization for low-mixing, intermediate-mixing, and high-mixing categories is 0–360 ms, 360 ms–1400 ms, and 1400 ms–2400 ms, respectively. Iso-efficiency lines demarcate all the three classes.