Design and implementation of an annular acoustic levitation system

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2014
Kandemir, Mehmet Hakan
In standing wave acoustic levitation technique, a standing wave is obtained between a source and a reflector. Particles can be attracted towards pressure nodes in standing waves owing to the spring action. Hence, particles can be suspended in air. This operation can be performed on continuous structures as well as in several numbers of axes. In this study an annular acoustic levitation set-up is designed and built. The set-up consists of two langevin type piezoelectric transducers, two waveguides, an annular plate, an annular concave reflector, supporting structures, a signal generator and a power amplifier. The transducers are activated by harmonic signals generated by a signal generator and amplified by an amplifier to excite the waveguides. The waveguides amplify the vibration amplitude and in turn, excite the annular plate to a bending mode at a certain frequency. As the plate vibrates in bending mode, it excites the air and generates sound waves. Several types of bending modes of the plate are simulated and evaluated. With the right positioning of the reflector plate, standing waves are formed between the annular vibrating plate and the reflector plate. At the pressure nodes of the standing wave, it is demonstrated that small particles can be suspended in air.

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Citation Formats
M. H. Kandemir, “Design and implementation of an annular acoustic levitation system,” M.S. - Master of Science, Middle East Technical University, 2014.