Design and verification of a KNN-based vibrating mesh atomiser

Abstract

Inhalation therapy in which drugs are delivered directly to targeted sites is a crucial approach for treating common respiratory diseases. As crucial devices for inhalation therapy, traditional medical nebulisers typically employ lead-containing atomizing discs that cause pollution and harm to the environment and human health during production and use. In this study, a (K,Na)NbO₃ (KNN)-based micromesh nebuliser utilising lead-free KNN piezoelectric ceramic as the atomisation disc material was designed to enhance nebuliser performance through methods such as doping. We investigated the resonant frequency and mode of vibration for each order of atomisation disc vibration through finite element analysis and validated the accuracy of the developed model through comparisons with experimental results. Further validation of the microorifice theory was achieved through atomisation experiments, and the impact of the atomisation disc parameters and input signals on atomisation was analysed. Additionally, empirical formulas for the atomisation rate and pore number were derived. Under square wave pulses with a voltage of 80 V, duty cycle of 50 %, and frequency of 137 kHz, the median particle size of the atomised particles was 3.0 μm with an atomisation rate of 0.3 ml/min.