Experiments and simulations of the standing wave acoustic field produced by two transducers mounted in contraposition

Acoustic standing wave levitation transmission technique has been widely used in many research areas. In this work, two Langevin-type piezoelectric transducers' output are assembled face to face at a certain angle. Each transducer's output acts as both its radiator and another transducer's reflector. The authors termed it as contraposition transducer array. Standing acoustic wave in the cavity between the radiator and the reflector is formed when optimizing the angle between the central lines of the two transducers, the distance of the cavity, and the phase differential of the generator being used to excite the two transducers. Accordingly, the object during the acoustic field can be levitated, moved and manipulated. Not only the standing acoustic field pressure is theoretically derived, but also its potential location is Ansys-programmed simulated and illustrated. As a result, the restrictions are detailed which are necessary to form the standing acoustic wave. The corresponding experiments are carried out to demonstrate the proposed method by the authors. Finally, the influences of geometrical parameters and exciting phase differential on the formed acoustic field are numerically simulated.