Piezoelectric Energy Harvesting from Ultrasonic Vibration in Fluid Environments

This paper presents the development of piezoelectric energy harvesting from ultrasonic vibration in fluid environments. The ultrasonic is emitted by the transducer in the ultrasonic cleaner and propagated in fluid environments which causes the piezoelectric bimorph bending up and down, thus the PZT layer generates electrical charges. Some preliminary experiments including output voltages in different fluid environments and in draft angles of the piezoelectric device relative to the level surface have been investigated. The experimental result shows that the output voltages vary with the fluid environment, the maximum voltage is generated in clean water and then physiological saline and sea water. Additionally, different draft angle lead to various output voltages with the maximum voltage been present at 45 degrees to 60 degrees or 105 degrees to 120 degrees region and the minimum value at 90 degrees in the same fluid environment. Some possible causes about this phenomenon are also analyzed.