Measurement of two-phase velocities in bubble flows using laser Doppler velocimetry  

作　　者：Ling-xin Zhang Xin-sheng Cheng Han Tu Qi Gao Xue-ming Shao Xiang-Wei Liao Liang Zhao 

机构地区：[1]Department of Engineering Mechanics,Zhejiang University,Hangzhou,310027,China [2]Iron and Steel Research Institutes of Ansteel Group Corporation,Anshan,114009,China [3]State Key Laboratory of Metal Material for Marine Equipment and Application,Anshan,114009,China

出　　处：《Journal of Hydrodynamics》2022年第6期1134-1144,共11页水动力学研究与进展B辑（英文版）

基　　金：Project supported by the State Key Program of National Natural Science of China(Grant No.91852204);supported by the Program of State Key Laboratory of Marine Equipment(Grant No.SKLMEA-K201910).

摘　　要：The measurement of two-phase velocities in bubble flows using laser Doppler velocimetry(LDV)is studied.The key to the problem is to differentiate the LDV signals from bubbles and tracers,based on which the two-phase velocities can be characterized.In this study,two experiments are carried out.Firstly,the bubble-chain experiment is performed to investigate the optical response of bubble surface and the corresponding LDV signal.The optical response shows that the light received by the LDV detector is dominated by the reflection component,which is similar to specular reflection to some extent.There are three typical patterns of signals of large bubbles passing through the measurement volume,all of which are with high amplitude and saturated.Then,the upward-flow experiment is conducted to study the statistical characteristics of large bubbles as well as micro tracers and micro bubbles.The results show that the amplitude of signal of millimeter bubbles is about an order of magnitude larger than that of tracers or micro bubbles.Based on this significant difference of the amplitude,we propose a phase discrimination method to distinguish two-phase signals.The capability of the proposed method is tested in a complex bubble flow,and its reliability is verified by bubble tracking velocimetry(BTV)technology.

关 键 词：laser Doppler velocimetry(LDV) bubbly flow phase discrimination bubble tracking velocimetry(BTV) 

分 类 号：O358[理学—流体力学]