Abstract:The evolution process of drop formation in another immiscible oil during dispersive liquid atomization is experimentally studied by image gathering and processing. The results show that there exist three typical dispersive liquid break-up forms related to drop formation, dripping, laminar jet and turbulent motion jet, with three different mechanisms. The variation of liquid-liquid atomization forms, jet break-up intensity, jet length fluctuation and drop size distribution with liquid Reynolds number (Re) and Weber number (We) show that jet break-up intensity is strengthened continually with increasing of Re and We, dispersive liquid break-up form is transformed from the dripping to laminar jet at Re=467 and We=8.6, and becomes finally the turbulent motion jet at Re=3169 and We=241, and the best spreading parameters of drop size distribution, the uniformity and least mean value of drops size, always appear in turbulent jetting form. Under the dripping form, emerging, developing and breaking away of liquid drops from the tip of nozzle are dominated by balanced-force mechanism. And under the laminar jetting form, the mechanism of dispersive liquid break-up is caused by interphase surface wave motion, and jet length fluctuation is characterized by random and no periodic ways. However, under the turbulent jetting form, coherent structure appears and acts on jet instability at the initial section of the jet, and a large number of finer drops form in the diffusion section.
梁坤峰 王林 阮春蕾 徐斌. 液-液分散雾化形成液滴的模式[J]. , 2013, 13(5): 735-741.
LIANG Kun-feng WANG Lin RUO Chun-lei XU Bin. Evolution of Drop Formation Form in Another Liquid during Dispersive Liquid Atomization. , 2013, 13(5): 735-741.