Liquid Jet Breakup by High-Frequency Pressure Modulation

We developed a system for the mass production of µm-size liquid particles. Liquid jet is emitted by a glass nozzle with a constant pressure and the additional pressure modulation induced by an ultrasonic transducer causes a slight periodical change in jet radius: the modulation spontaneously evolves and the jet breaks up into µm particles. By applying the modulation at a frequency higher than 100 kHz to the nozzle with an inner diameter of 8 µm, we succeeded in producing pl-size particles at a rate of 105 particles/s. We also demonstrated the ability of our system to produce microcapsules by the collision of liquid particles.