借助影像处理软件PFV和图像处理软件Image-Pro Plus,详细分析了高速摄像仪获取的文丘里管气泡发生器内气泡的输运及破碎过程。研究表明:文丘里管气泡发生器内气泡的破碎过程存在2个明显的不同阶段;气泡在扩张段入口处存在明显的减速过程,且在减速过程中存在3种主要的形变过程;气泡的减速过程对气泡的碎化存在重要影响;气泡在扩张段的迅速减速,造成了气-液之间的运动速度差迅速加大,极大强化了气-液之间的相互作用,致使在扩张段较大直径的气泡迅速碎裂成大量的微小气泡。
In order to illustrate the mechanism and process of bubble breakup in a venturi-type equipment for generating bubbles, the transportation and breakup process of bubbles in a venturi-type bubble generator is analyzed in detail with the help of image and video processing softwares of PFV and Image-Pro Plus. It is found that two distinguished stages of bubbles exist in the generator; Bubbles will be decelerated rapidly at the entrance of the expansion section, during which three different kinds of deformation may occur to the bubbles. It is believed that the deceleration of bubbles has a significant effect on the bubble breakup process. The rapid deceleration of bubbles in the expansion section results in the increasing of the velocity difference and intensifies the interaction between the gas and liquid, leading to the bubbles with relatively large diameter breaking up into a great many tiny bubbles.