Bubble dynamics of flow boiling in microchannel within ultrasonic field

Flow boiling in the microchannel within ultrasonic field is demonstrated as a promising method to address the heat dissipation challenges encountered in microelectronic devices. However, bubble dynamic behavior under ultrasound and its associated mechanism remain largely unexplored. Here, we monitor bubble behaviors under the acoustic field and present the bubble dynamics model. Our observations unveil the unprecedented enhancement of bubble detachment when contrasted with scenarios devoid of ultrasound. This enhancement manifests as a three-order of magnitude reduction in growth time and a fiftyfold increase in sliding velocity, which is paramount to the enhancement of thermal performance. Furthermore, the force model is constructed to elucidate the mechanism of acoustic radiation force, namely primary Bjerknes force and secondary Bjerknes force, acting on bubble behaviors. This finding explores the intricate bubble dynamics within the ultrasonic field, providing valuable insights into the design of new cooling methods for microelectronic devices.