Observations of Non-Rayleigh Limit Explosions of Electrodynamically Levitated Microdroplets

Explosions far below the Rayleigh limit of charge were observed while levitating liquid microparticles in a double-ring electrodynamic balance. Video tapes of these novel explosions showed that when fission occurred a stream of many small droplets was emitted from the parent drop for several seconds. It was estimated that hundreds of daughter droplets were emitted during the event. Prior to fission, the droplets had radii of ∼ 15 μm and surface charge densities as low as ∼ 3% of the Rayleigh limit of charge. It is demonstrated that the explosions are not consistent with a variety of charge-loss mechanisms that were explored, and it is suggested that droplet fission may be due to localized heating and/or chemical reaction.