低喷淋密度下水平管降液膜速度演变规律的实验研究  

Experimental Study on the Evolution of Downcomer Film Velocity in Horizontal Tubes at Low Spray Density

作　　者：张广文 Zhang Guangwen(State Key Laboratory of Chemical Safety,Shandong,Qingdao,266104;SINOPEC Research Institute of Safety Engineering Co.,Ltd.,Shandong,Qingdao,266104)

机构地区：[1]化学品安全全国重点实验室,山东青岛266104 [2]中石化安全工程研究院有限公司,山东青岛266104

出　　处：《安全、健康和环境》2025年第2期37-45,共9页Safety Health & Environment

基　　金：国家自然科学基金青年项目(52106123),微液滴与薄液膜耦合强化低浓度H_(2)S热质传递的机理研究。

摘　　要：水平管降液膜因气液界面波动大、界面可精确控制等优点在吸收与传热等领域得到了广泛应用。研究低喷淋密度下的液膜速度演变规律,对于理解反应器微观传质机理,强化热质传递有重要意义。通过改进粒子图像测速(PIV)方法,对不同操作参数下的液膜速度演变规律进行了细致研究,发现水平管降液膜在不同流型下存在典型的分区特性。对于低流量的滴状流,在非撞击区,液膜的运动基本停滞,速度一直维持在0~0.1 m/s;而在撞击区,液膜速度先增大后减小,在50~60 ms时,液膜运动速度最大,可达0.6~0.7 m/s。滴状流时,喷淋密度对液膜速度的影响是通过减小液滴撞击频率,而非增加单个液滴的撞击速度,且喷淋高度对液膜铺展速度的影响可忽略。对于高流量的柱状流,液膜速度维持均匀分布,但在液膜交汇区,液膜速度会略高于主体运动区。柱状流的液膜铺展速度随喷淋密度和喷淋高度的增加而迅速增大。该研究有助于深入理解低浓度气体吸收强化机理,推动高效、紧凑型应急吸收装备的研究。The downcomer films of horizontal tubes have been widely used in the fields of absorption and heat transfer because of the large fluctuation of the gas-liquid interface and the precise control of the interface.It is of great significance to study the evolution law of liquid film velocity under low spray density for understanding the mechanism of micro-mass transfer in reactor and strengthening heat and mass transfer.By using the improved particle image velocimetry(PIV)method,the evolution of liquid film velocity under different operating parameters was studied in detail,and it was found that the horizontal downcomer film had typical zoning characteristics under different flow patterns.For droplet flow with low flow rate,in the non-impact zone,the motion of liquid film basically stagnated,and the velocity was maintained at 0~0.1 m/s.In the impact zone,the liquid film velocity increased first and then decreased.At 50~60 ms,the liquid film velocity reached the maximum,up to 0.6~0.7 m/s.In droplet flow,the effect of spray density on liquid film velocity was to reduce the droplet impact frequency rather than to increase the impact velocity of a single droplet,and the effect of spray height on liquid film spreading velocity can be ignored.For the high-flow cylindrical flow,the liquid film velocity was uniformly distributed,but in the liquid film intersection area,the liquid film velocity was slightly higher than that in the main body motion area.The spreading velocity of liquid film in cylindrical flow increased rapidly with the increase of spray density and spray height.This research further supported the efficient mass transfer process of thin liquid film absorbing toxic gases,and promoted the development of efficient and compact emergency absorption equipment.

关 键 词：水平管 降液膜 微液滴 低喷淋密度 速度 粒子图像测速(PIV) 

分 类 号：X511[环境科学与工程—环境工程]