Fig. 22. Microbubble production by flow focusing. (a) A schematic drawing, and (b) microscopic image of flow focusing geometries. In (a), QD, QC, and Wup represent the gas flow rate, liquid flow rate, and distance between the device wall and the gas channel, respectively. In (b), the orifice width, the gas flow channel width, and the junction-to-orifice distance is shown by WOR, 2a, and ΔZ, respectively.154.
