Investigation of operational parameters on the motional behavior and maximum particle levitated density in ultrasonic levitation

Ultrasonic levitation has a high potential to be used in different applications due to its independence from the levitated material. Among effective parameters of this process, the distance between the reflector and the transducer and applied voltage plays an important role in the process. Presenting a precise numerical model would be helpful in the study of the process. The levitated particle conditions as well as the levitated capacity, such as the maximum levitated particle density, can be predicted using the model. In this paper, a precise numerical model was presented to study of the process. In the model, by simultaneous solving the equations of the piezoelectric and the wave equation in the solid and fluid medium as well as considering the three-dimensional levitation and particle tracing in Comsol software, the simulation conditions were similar to the experiments. Hence results agreed well with the experimental results. The effect of voltage and distance between the transducer and the reflector on the levitated particle was investigated using the model. Particle motion during levitation was explained simply and effectively using the proposed certain parameters. Defining the parameters makes it possible to compare the particle conditions at different voltages and distances between the transducer and the reflector. The results showed that in order to properly levitated object condition, the adjustment of the parameters should be made based on each other's values. Moreover, the maximum density in different working conditions with an accuracy of 0.45% was presented using the proposed numerical model and halving algorithm.