【作者】 刘夷平； 王淑华； 张华； 王经；

【Author】 LIU Yi-ping WANG Shu-hua ZHANG Hua WANG Jing (Institute of Engineering Thermo-Physics,School of Mechanical Engineering,Shanghai Jiaotong University,Shanghai 200030)

【机构】 上海交通大学机械与动力工程学院工程热物理研究所；

【摘要】 水平气液两相流中,气相流速较高时出现的伪段塞流具有环状流和段塞流双重特征, 导致流型识别上的困难．利用压力脉动、压力信号的振幅、液塞的速度三种特征来辨识伪段塞流和段塞流,并应用于40mm 和50mm 管径水平管道空气-水两相流实验．在压力脉动时序图上,段塞流具有伪段塞流所没有的维持段特征,而且其压力振幅和液塞速度都要明显低于段塞流．在不同的流速区域,段塞流形成机理不同,在较高的气相表观速度下,判断段塞流出现的依据在于其上游的液层能否提供足够的液体来维持一个稳定的段塞体单元．根据段塞稳定性理论,对段塞流出现的临界条件进行了理论预测,结果和实验数据相比较为吻合, 而且流型转交曲线能较好地将段塞流和伪段塞流区域区分开来．更多还原

【Abstract】 In two-phase gas-liquid horizontal co-current flow,pseudo-slug flow is observed at higher gas velocities.This pattern resembles annular flow in that a continuous liquid film is formed on the pipe circumference,while it is identified as disturbances which have the appearance of slugs. Therefore,it is difficult to distinguish visually with ordinary method.By the analysis on pressure-fluctuation and distinctive features of slugs,three characteristics combined to detect of slug flow are adopted and applied to the experiment about air-water two-phase flow in horizontal 40 and 50 mm pipes.In pressure-fluctuation measurements,slug flow features an approximately unchanged pressure section while pseudo-slug does not.The amplitudes and translation velocities of pseudo-slugs are much lower than those of slugs.The forming mechanisms of slug vary with different ranges of gas flows.At higher gas superficial velocities,the onset of slug depends on the liquid flow upstream which is enough to maintain a stable slug unit.Slug stability model is used to predict the transition to slug flow,and the results show that better agreement has been achieved between predicted and measured patterns,and curve of flow regime transition distinguishes slug flow from pseudo-slug flow.更多还原