基于图像处理的管束间气液两相含气率的实验研究

Investigation on Gas-liquid Two-phase Flow Void Fraction Across Tube Bundles Based on Images Processing Method

将数字图像处理方法应用到管束间气液两相流动含气率的检测并研究其分布特性。采用高速摄影仪,拍摄管束间气液两相流动的流型图像,利用图像处理技术对流型图像进行灰度增强、二值化、边缘检测等处理,然后计算出两相流动不同时刻的含气率。实验结果表明,该方法能够满足测量要求,可以用于管束间两相流动参数的检测。将2种管束的含气率值与模型预测结果比较,发现Feenstra模型和Dowlati模型能较好地预测含气率。比较管束不同方向的含气率分布特性,发现壁面位置含气率低,管束中心含气率高。

Digital image processing method was used to detect void fraction and study the distribution characteristics of gas-liquid two phase flow in tube bundles.High-speed camera system was employed to capture the real-time images of gas-liquid flow. Image processing technology was adopted to gray enhance, edge detection and binarization in the images. Thus, parameters of image were calculated. Experimental results show that the method has high measurement accuracy, and can be used for detection of parameters in gas-liquid flow. Comparisons with the literature available show that the Feenstra model and Dowlati model provides the best agreement with experimental data. Void fraction is low on surface position and high in center of tube bundle, which is observed by comparison of different direction of tube bundle.