Void fraction measurement using NIR technology for horizontal wet-gas annular flow
Void fraction measurement using NIR technology for horizontal wet-gas annular flow
复制标题
使用 NIR 技术测量水平湿气环流的空隙率
DOI：
10.1016/j.expthermflusci.2016.03.014
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发表时间：
2016
影响因子：
3.2
通讯作者：
Feng Yue
中科院分区：
文献类型：
--
作者：
Wang Chao;Zhao Ning;Fang Lide;Zhang Tao;Feng Yue
由于持水率低，湿气环流的空隙率很难测量。近红外（NIR）光谱对水具有特征吸收带，可以提高湿气环流空隙率测量中对水的敏感性。本文提出了一种基于近红外光谱的空隙率测量方法。本文设计了一种非侵入式传感器。根据H2O的特征O-H吸收带，选择970 nm作为NIR光源的发射波长。考虑液膜的吸收、夹带液滴的散射和两相界面反射，构建并进一步简化了基于近红外透射率的空隙率模型。利用简化模型和设计的传感器，获得了 0.4 MPa 和 0.5 MPa 管道压力下 48 个水平湿气环流条件下的空隙率测量结果。实验室结果表明，测量模型的相对偏差范围为-5.53%至7.34%，但93.75%的相对偏差在±5%以内。
It is difficult to measure the void fraction of wet-gas annular flow due to the low water holdup. The near infrared (NIR) spectrum has characteristic absorption band for water, which can increase the sensibility to water in the void fraction measurement of wet-gas annular flow. This paper presents a void fraction measurement method based on NIR spectrum. A non-invasive sensor was designed in this paper. According to characteristic O–H absorption band of H2O, 970 nm was selected as the emission wavelength of NIR light source. Considering absorption of liquid film, scattering of entrained droplets and interface reflection of two-phase, a void fraction model base NIR transmittance was constructed and further simplified. Utilizing the simplified model and designed sensor, void fraction measurements had been obtained for 48 horizontal wet-gas annular flow conditions in the pipeline pressure of 0.4 MPa and 0.5 MPa. Laboratory results indicate that the relative deviations of the measurement model range from −5.53% to 7.34%, but the 93.75% of relative deviations are within ±5%.