Enhanced acoustic levitation using horn loaded and focusing radiators

Abstract

An improved piezoelectric driven, focusing acoustic radiator for acoustic levitation has been designed, tested, and evaluated. This device displays a significant improvement in focusing to produce better specimen stability and energy well shaping as well as increased transducer power bandwidth and electroacoustic conversion efficiency. Corresponding effects resulting from the horn loading of this acoustic radiator are considered as well as the benefits of using the radiator in conjunction with hot wall high-temperature furnaces. In order to aid in the evaluation of these acoustic transducer improvements, a simple and useful technique for acoustic field mapping will also be discussed. [Work supported by NASA.]