In recent years, more and more actuators based on cavitation bubbles are developed for microfluidic chips to implement various functions, such as sorting cells and mixing the flows. However, the dynamic properties of cavitation bubbles in microfluidic chips have not been systematically studied. Using voltage-controlled sparks to trigger cavitation bubbles in a microfluidic chamber, this work studies the relationship between the bubble size and the input energy, the effect of the aqueous solution conductivity on the bubble size, the repeated spark actions, and the necessity of the buffer flow to keep the repeated cavitation steady. The findings in this work reveal how to generate individual cavitation bubble inside microfluidic chips in a controllable way, which can contribute to creating new microfluidic actuators driven by cavitation bubbles.

近年来，越来越多的基于空化气泡的致动器用于微流控芯片，以实现各种功能，例如分选细胞和混合流。但是，尚未对微流控芯片中空化气泡的动力学特性进行系统研究。使用电压控制的火花在微流体室内触发气穴气泡，这项工作研究了气泡尺寸和输入能量之间的关系，水溶液电导率对气泡尺寸的影响，重复的火花作用以及是否需要缓冲液流动以保持反复的空化稳定。这项工作的发现揭示了如何以可控的方式在微流控芯片内部产生单个的气蚀气泡，这可以有助于创建由气蚀气泡驱动的新型微流体致动器。