Instability of electrically stressed water droplets in oil

The breakup of water droplets in an electric field has been studied in naphtenic oil as a function of water conductivity and surface tension of the droplets, and frequency and waveform of the applied voltage. The critical breakup field compares well to theoretical values for low voltage frequencies, but large deviations are found for frequencies above 100 Hz. Four different instability modes are observed at droplet breakup.