Gas Bubble Sizes Formed in Liquids at Different Resonant Frequencies

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. 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.