FREQUENCY DEPENDENCE OF LEVITATION FORCE IN NEAR-FIELD ACOUSTIC LEVITATION

抄録

Near-field acoustic levitation is a method to levitate an object in a close range by utilizing vibration of the object or the ground surface at a high frequency. In this paper, the frequency dependence of levitation force is numerically and experimentally investigated, which is important for the fundamental understanding of near-field acoustic levitation and the design optimization for non-contact actuators and bearings based on the phenomenon. Computational fluid dynamics simulation is used to study a simplified two-dimensional model. It is found that the levitation force reaches local maximal values at multiple critical frequencies, which is associated with the pressure distribution pattern within the air film. The nonlinear relationship between the levitation force and frequency is verified through the experimental study. The first critical frequency corresponding to the maximum levitation force has been successfully identified in the experiment.