Experiments were conducted to investigate the inner structure of gas–liquid flow in airlift pumps by a laser Doppler velocimetry (LDV) system and a laser‐high speed photography. The measured central plane of the riser pipe was illustrated by a laser device, and the corresponding gas–liquid flow in this plane was recorded by a high speed camera. The results showed it was the wispy annular flow, rather than the annular flow, dominated the pump performance under a high gas flow rate. This wispy annular had a thick film with a maximal value 0.2 times of pipe diameter, and it kept pump working with a high output liquid flow rate at large gas flow rates. Moreover, new flow regime maps were presented with a function of accurately estimating the flow regime transition and presenting the airlift pump performance.

中文翻译：

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激光高速可视化技术研究气举泵内气液流动的内部结构

通过进行激光多普勒测速（LDV）系统和激光高速摄影，对气举泵中气液流动的内部结构进行了实验。测得的立管中心平面由激光设备显示，该平面上相应的气液流量由高速摄像机记录。结果表明，在高气体流量下，细小的环形流而不是环形流主导了泵的性能。这个细小的环状物具有厚膜，其最大值是管直径的0.2倍，并且使泵在大气体流量下仍以高输出液体流量工作。此外，还提供了新的流态图，其功能是准确估算流态转换并显示气举泵性能。