Finite element simulation of contact-impact dynamics for high-power ultrasonic processing system

Nonlinear contact-impact dynamic behavior of high-power ultrasonic processing systems is studied in experiment and theory. Firstly, nonlinear contact-impact vibrations in a high-power ultrasonic processing system are studied experimentally. Then a finite element method is used to analyze the observed experimental phenomena, in which a 2D axisymmetric model is developed, and the nonlinear contact-impact dynamic behavior is analyzed. The finite element method simulation results of the contact-impact behavior between the transducer horn and the sample show that the contact force between the horn tip and the sample is very complicated and includes super- and sub-harmonic frequency components in addition to the ultrasonic excitation frequency. The subharmonic vibrations in the samples are simulated in detail, and the results show that the subharmonic vibrations will always occur as observed in the experiments.