文献类型：期刊文献

英文题名：Thickness distribution of decay swirl liquid film and its fluctuation characteristics in a vertical tube

作者：Zeng, Jie[1];Wang, Yifei[1];Feng, Dawei[1];Liu, Qian[1];Gong, Yan[1];Yu, Guangsuo[1];Wang, Fuchen[1]

机构：[1]East China Univ Sci & Technol, State Key Lab Coal Liquificat Gasificat & Utilizat, Shanghai 200237, Peoples R China

年份：2025

卷号：218

起止页码：794

外文期刊名：CHEMICAL ENGINEERING RESEARCH & DESIGN

收录：;EI(收录号：20252118479983);WOS:【SCI-EXPANDED(收录号:WOS:001500386100001)】；

语种：英文

外文关键词：Swirl liquid film; Film thickness distribution; Statistical properties; Decay swirling flow; Film thickness prediction

摘要：The liquid film thickness distribution of vertical and swirling flow and its fluctuation characteristics were investigated using ultrasonic Doppler velocimetry and a high-speed camera under superficial liquid velocity (U-sl) of 0.58-1.21 ms(-1). Predicted correlations for mean liquid film thickness were established in the development region as a function of the dimensionless axial distance (x/D). The results show that vertical flow trajectories align with gravity while swirling flow exhibits curved trajectories. Increasing U-sl decreases the circumferential liquid film uniformity of the vertical flow, with a maximum relative standard deviation (RSD) of 15.95 %. In contrast, the swirl-inducing elements and higher U-sl increase the number of swirling streaks, enhancing circumferential uniformity (with a maximum RSD = 4.03 %). Rapid thinning of the liquid film occurs within x/D < 0.89, independent of the flow pattern and U-sl. Swirling flow's centrifugal force reduces the liquid film fluctuations compared to vertical flow. The minimum dimensionless liquid film thickness in the main heat transfer zone is approximately 0.6 for vertical flow and 0.8 for swirling flow. The predictive correlations accurately predict the mean liquid film thickness with a relative error within +/- 15 %.