Acoustic levitation of an object larger than the acoustic wavelength

Author(s)

Andrade, Marco A. B. ; Okina, Fabio T. A. ; Bernassau, Anne L. ; Adamowski, Julio C.

• Document type: Journal article
• Source: JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA; v. 141, n. 6, p. 4148-4154, JUN 2017.
• Web of Science Citations: 8

Abstract

Levitation and manipulation of objects by sound waves have a wide range of applications in chemistry, biology, material sciences, and engineering. However, the current acoustic levitation techniques are mainly restricted to particles that are much smaller than the acoustic wavelength. In this work, it is shown that acoustic standing waves can be employed to stably levitate an object much larger than the acoustic wavelength in air. The levitation of a large slightly curved object weighting 2.3 g is demonstrated by using a device formed by two 25 kHz ultrasonic Langevin transducers connected to an aluminum plate. The sound wave emitted by the device provides a vertical acoustic radiation force to counteract gravity and a lateral restoring force that ensure horizontal stability to the levitated object. In order to understand the levitation stability, a numerical model based on the finite element method is used to determine the acoustic radiation force that acts on the object. (C) 2017 Acoustical Society of America. (AU)

• FAPESP's process: 15/08919-9 - Numerical and experimental study of near-field acoustic levitation
• Grantee: Fábio Takeshi Asakura Okina
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• FAPESP's process: 14/24159-1 - Noncontact particle manipulation by ultrasound
• Grantee: Marco Aurélio Brizzotti Andrade
• Support Opportunities: Regular Research Grants