【摘要】 本文采用高速摄影仪对滞止流体中毛细管管口的气泡生长和脱离过程进行了可视化实验研究.实验结果表明:气泡生长脱离过程包括生长初期、快速生长期、缓慢生长末期等三个区域,气-液相界面的接触角随之产生相应的变化.随着毛细管管径的增大,气泡的脱离直径随之增大,生长脱离周期减小;气流量越大,气泡脱离直径越大,生长脱离周期越小;注气室容积变化对气泡的脱离直径影响很小,但随着注气室容积增大,气泡的生长脱离周期增大.更多还原

【Abstract】 The bubble growth and detachment at the tip of a capillary tube in stagnant fluid was ex- perimentally investigated by using a high-speed visual system.The visualization experimental results show that the growth of the bubble experiences three typical stages:initial growth,speedup growth, and speed-down growth accompanying with varying contact angles.The contact angle decreases with the bubble growth to reach near 50 degree and then increases quickly to reach near 140 degree accom- panying with the detachment of the bubble from the neck of liquid.The detachment diameter of the bubble increases while the detachment period decreases with an increase in the internal diameter of the capillary tube and the gas flow rate.The volume of gas injection chamber has little influence on the bubble detachment diameter while the detachment period increases with increasing volume of the gas injection chamber.更多还原