Finite element analysis and optimization of a single-axis acoustic levitator

• Published in: IEEE transactions on ultrasonics, ferroelectrics, and frequency control Vol. 57; no. 2; pp. 469 - 479
• Main Authors: Andrade, M.A.B., Buiochi, F., Adamowski, J.C.
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01-02-2010; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Acoustic radiation; Acoustic transducers; Acoustical engineering; Acoustics; Aluminum; Boundary conditions; Ceramics; Computer simulation; Electric potential; Exact sciences and technology; Finite element analysis; Finite element method; Finite element methods; Fundamental areas of phenomenology (including applications); Mathematical analysis; Mechatronics; Nonlinear acoustics, macrosonics; Physics; Piezoelectric actuators; Piezoelectric transducers; Planes; Reflectors; Studies; Transducers; Voltage; Plane surface; Energy consumption; Steel; Modeling; Vibrometer; Optimization; Concave antenna; Finite element method; Sphere; Optical measurement; Displacement measurement; Acoustic radiation; Curvature; Ultrasonic transducer; Optical fiber; Electrical impedance
• ISSN: 0885-3010; 1525-8955
• DOI: 10.1109/TUFFC.2010.1427

A finite element analysis and a parametric optimization of single-axis acoustic levitators are presented. The finite element method is used to simulate a levitator consisting of a Langevin ultrasonic transducer with a plane radiating surface and a plane reflector. The transducer electrical impedance, the transducer face displacement, and the acoustic radiation potential that acts on small spheres are determined by the finite element method. The numerical electrical impedance is compared with that acquired experimentally by an impedance analyzer, and the predicted displacement is compared with that obtained by a fiber-optic vibration sensor. The numerical acoustic radiation potential is verified experimentally by placing small spheres in the levitator. The same procedure is used to optimize a levitator consisting of a curved reflector and a concave-faced transducer. The numerical results show that the acoustic radiation force in the new levitator is enhanced 604 times compared with the levitator consisting of a plane transducer and a plane reflector. The optimized levitator is able to levitate 3, 2.5-mm diameter steel spheres with a power consumption of only 0.9 W.