APPLICATION OF PIEZOELECTRIC MICRO BUBBLE GENERATOR TO BLOOD OXYGENATION

摘要

The present research applies the microelectronmechanical system (MEMS) technology to design and fabricate a novel micro-bubble generator by using a piezoelectric actuator. The main structure of the proposed generator adopts an annular piezoelectric ceramic which is coupled with a nickel nozzle plate. When an electric field is applied across the thickness of the generator, the piezoelectric element deforms transversely. The radial strain causes the surface of the nozzle plate to expand or contract, which causes the entire structure to bend, and in turn transport oxygen micro-scaled bubbles into the blood flow for enhancing the oxygen content in blood. In the experiment, a flow visualization setup employs a high magnification microscope and a high speed charge coupled device (CCD) camera to photograph the time evolution of meniscus shape of gaseous bubbles dispensed from the micro-bubble generator. The bubble formation process including the effects of inlet gas pressure as well as driving voltage and resonance frequency on generated bubble size is also discussed in the study.