  The generation of single, monodisperse compound droplets is shown in these
fluid dynamics videos. In an apparatus designed to produce single compound
droplets, a piezoelectric diaphragm generates a pressure pulse from a voltage
waveform input to eject a droplet. In the method presented, oil is allowed to
flow into the water nozzle with the pressure pulse ejecting both fluids as a
compound droplet. Experiments were performed to demonstrate how changes in
water pressure affect compound droplet compositions. It was found that
increasing the water pressure decreased the thickness of the compound droplet's
oil layer.
