Fluid-structure coupling analysis and simulation of a micromachined piezo microjet

A piezoelectric microjet has been fabricated and its working mechanism has been investigated. Considering different physical effects, the coupling models of the device are established and the key characteristics of the microjet are simulated by finite-element method. The dynamic displacement responses of the transducer under liquid-loading and unloading are calculated and compared. From numerical results, while the coupling interactions dramatically damp the vibration amplitude of the transducer, the effects on the resonant frequencies of the structure are negligible, which is very important for further design optimization of the device. Based on the optimal design rules, the device has been fabricated and characterized.