Ultrasonic Levitation by Stepped Circular Vibrating Plate

Abstract

A high intensity ultrasound field was produced by a new type sound source called a stepped circular vibrating plate, and the experimental results on levitation in air by ultrasound energy are described. The density of samples, frequencies and sample dimensions were varied. The minimum threshold of sound pressure required for levitating the samples was found proportional to sample density, and was also inversely proportional to the ultrasonic frequency used.