Droplets generation by a torsional bolt-clamped Langevin-type transducer and micropore plate

In this study, a torsional bolt-clamped Langevin-type transducer has been used for generating micro droplets. A plate which had a micropore and was attached at the tip of the transducer was oscillated by the transducer. By using torsional vibration, many micropores can be oscillated uniformly. When the micropore plate was not oscillated, droplets were generated irregularly. On the contrary, when a micropore plate was oscillated, droplets were generated regularly. When the pore diameter, the vibrational amplitude and the resonance frequency were 16 mum, 0.62 mum_p-p and 56 kHz, respectively, the averaged diameter of droplets was 26.8 mum. The standard deviation of the diameter was 1.41. In addition, by using this transducer, W/O (Water-in-Oil) emulsions were generated in air-liquid phase. Under the same condition, the averaged diameter of emulsion was 35.0 mum, the standard deviation was 1.9 and the coefficient of variance was 5.5.