(671g) Dynamic Interfacial Tension during Droplet/Bubble Generation at Microchannel Junctions - an Important Mesoscale Scientific Issue in Multiphase Microflow Study

The dynamic interfacial tensions caused by surfactant adsorption and chemical reactions during droplet/bubble generation process at microchannel junctions are important mesoscale scientific issue between molecule and microchannel scales. This phenomenon exhibits the variations of interfacial composition during fluid particle generations with chemical processes, which is commonly taken place in microflow reaction and separations. This presentation gives a summary of our recent studies focusing on the determination of dynamic interfacial tension at during the droplet and bubble generations T-shaped¹ and coflowing microchannel junctions², and the variation laws of interfacial compositions with several surfactant absorption processes³ as well as the chemical reaction of CO₂ and MDEA solution⁴. Experimental results show increase of decrease in interfacial tension from the static interfacial tension with equilibrium states. The Marangoni effect caused the gradient of dynamic interfacial tension is further exhibited by LBM simulations⁵, which is helpful for the understanding of multiphase microflow processes. Funding supports are from National Natural Science Foundation of China (21776150, 91334201, U1302271).

References:
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