Abstract We report on an experimental investigation of adiabatic bubbly two-phase flow development in a DN50 pipe with a ring-shaped and a baffle-shaped constriction at different superficial velocities of gas (up to jg = 0.1400 m·s−1) and liquid (up to jl = 1.6110 m·s-1) using ultrafast electron beam X-ray computed tomography (UFXCT). From UFXCT images, cross-sectional gas holdup distributions were obtained with a temporal resolution of up to 2,500 frames per second in 18 scanning planes along the pipe. A sophisticated data processing approach was applied to extract gas holdup data immediately from the two-phase flow image stack. Based on that, time-averaged gas holdup of the cross-section and the axial center of the pipe were calculated. In addition, bubble sizes and velocities were determined.

中文翻译：

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收缩垂直管中气泡两相流的研究

摘要 我们报告了在 DN50 管道中，在气体（高达 jg = 0.1400 m·s-1）和液体的不同表观速度下，具有环形和挡板形收缩部的绝热气泡两相流发展的实验研究（高达 jl = 1.6110 m·s-1）使用超快电子束 X 射线计算机断层扫描 (UFXCT)。从 UFXCT 图像中，可以在沿管道的 18 个扫描平面中以高达 2,500 帧/秒的时间分辨率获得横截面含气率分布。应用复杂的数据处理方法从两相流图像堆栈中立即提取含气量数据。在此基础上，计算了管道横截面和轴心的时均含气率。此外，还确定了气泡大小和速度。