FIG. 6.

Effect of impulse time and time gap between two successive impulses on size of droplet. Different gaps (τ=1 − 5 s) between two successive impulses at fixed flow rates are shown at 20 μl/h in the main channel and (a) 80 μl/h (b) 40 μl/h in the nozzle flow-by input channel. For each impulse time, statistical data on droplet volumes are collected up to 30 min. In the plot (a), the dashed black line shows the theoretical prediction of the equivalent circuit model (see Sec. III E), corresponding to long gap times (green 5 s curve). (c) Flow rates in side channel: 80 μl/h, central channel: 20 μl/h, impulse time: 0.1 s. After 4 s, the average size of droplet size stays constant (which is due to complete relaxation of interface).