A novel multiple drop levitator for the study of drop arrays

A novel acousto-electric levitator has been developed for studying various phenomena associated with drop arrays. In order to stably levitate a group of drops, charged drops are generated in an acoustic field. The acoustic radiation force draws charged drops toward a certain location; the electrostatic repulsion among the drops prevents droplet coalescence and produces a nearly uniformly spaced drop array. Measurements with single droplets allow for tests of the influence of the acoustic field on the droplet evaporation rates. Interference effects among drops are observed by measuring their evaporation rates in a droplet array. Measured rates in these preliminary tests of the new apparatus are slightly lower than predicted theoretically.