Experimental determination of the dynamics of an acoustically levitated sphere

Journal Article · Fri Nov 14 04:00:00 EST 2014 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.4901579· OSTI ID:22402643

Pérez, Nicolás ^[1]; Andrade, Marco A. B. ^[2]; Canetti, Rafael ^[3]; Adamowski, Julio C. ^[4]

---

1. Centro Universitario de Paysandú, Universidad de la República, Paysandú (Uruguay)
2. Institute of Physics, University of São Paulo, São Paulo (Brazil)
3. Facultad de Ingeniería, Universidad de la República, Montevideo (Uruguay)
4. Department of Mechatronics and Mechanical Systems Engineering, Escola Politécnica, University of São Paulo, São Paulo (Brazil)

Levitation of solids and liquids by ultrasonic standing waves is a promising technique to manipulate materials without contact. When a small particle is introduced in certain areas of a standing wave field, the acoustic radiation force pushes the particle to the pressure node. This movement is followed by oscillations of the levitated particle. Aiming to investigate the particle oscillations in acoustic levitation, this paper presents the experimental and numerical characterization of the dynamic behavior of a levitated sphere. To obtain the experimental response, a small sphere is lifted by the acoustic radiation force. After the sphere lift, it presents a damped oscillatory behavior, which is recorded by a high speed camera. To model this behavior, a mass-spring-damper system is proposed. In this model, the acoustic radiation force that acts on the sphere is theoretically predicted by the Gor'kov theory and the viscous forces are modeled by two damping terms, one term proportional to the square of the velocity and another term proportional to the particle velocity. The proposed model was experimentally verified by using different values of sound pressure amplitude. The comparison between numerical and experimental results shows that the model can accurately describe the oscillatory behavior of the sphere in an acoustic levitator.

• OSTI ID: 22402643
• Journal Information: Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 18 Vol. 116; ISSN JAPIAU; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
LEVITATION
LIQUIDS
MATERIALS
OSCILLATIONS
PARTICLES
SPHERES
STANDING WAVES
VELOCITY