A PIEZOELECTRIC ULTRASONIC ATOMISATION SYSTEM FOR PASSIVE HUMIDIFICATION DEVICE INTENSIVE CARE PATIENT APPLICATIONS

摘要

This paper presents a piezoelectric ultrasonic atomisation device for passive humidification device intensive care patient applications. The atomisation system is aiming to improve the passive humidification device heat and moisture exchange (HME) materials performance, by recovering the accumulated moisture, for a greater patient care. The atomisation device design, structure, working principles and analysis using finite element analysis (FEA) is discussed and presented in this paper. The computer simulation and modelling using FEA for the atomisation device has been used to examine the device design structure. It enabled to select the material of the vibration transducer, investigate the material deformation, defining the operating parameters and establish the working principles of the device. A working prototype has been fabricated to test the device, technical parameters, performance and practicality to utilise in such applications. Experimental tests showed that the electrical working parameters of the device are: Current: 50 m-amps, Voltage: 50 volts, Frequency: 41.7 kHz. The device integrated into the passive humidification device unit and initial results show some improvement in the HME materials and moisture return of the device by 2.5 mg per litre H_2O.