Formation of monodisperse bubbles in a microfluidic flow-focusing device

This letter describes a method for generating monodisperse gaseous bubbles in a microfluidic flow-focusing device. The bubbles can be obtained in a range of diameters from 10 to 1000 mum. The volume V-b of the bubbles scales with the flow rate q and the viscosity mu of the liquid, and the pressure p of the gas stream as V(b)proportional top/qmu. This method allows simultaneous, independent control of the size of the individual bubbles and volume fraction of the dispersed phase. Under appropriate conditions, bubbles self-assemble into highly ordered, flowing lattices. Structures of these lattices can be adjusted dynamically by changing the flow parameters. (C) American Institute of Physics.