垂直上升管汽液两相流型的压差波动特征识别

IDENTIFICATION OF FLOW REGIMES IN VERTICAL UPWARD STEAM - WATER TWO PHASE FLOW USING DIFFERENTIAL PRESSURE FLUCTUATIONS

运用现代数字信号处理技术,对垂直上升管水/水蒸气两相流不同流型时的压差波动信号特性进行了分析研究,提出了基于压差波动特征的两相流流型的客观识别方法。通过提取压差波动信号的功率谱分布特征,表明利用功率谱随频率的分布特性的均方根可客观识别出泡状流、间歇流和环状流。

The characteristics of differential pressure fluctuations in vertical upward steam - water two ?phase flow under the condition of high temperature and high pressure are studied by using the signal process technique. The fluctuations are analyzed by using the methods of time domain and frequency domain, which is a power spectrum density (PSD) function.The features of the curves of the power spectrum versus frequency are categorized as two kinds. The feature of the power spectrum density function is extracted by means of the Root Mean Square (RMS), from which an objective flow regime indicator is developed. The experimental result agrees well with the flow regime map proposed by McQuillan & Whal-ley under the pressure of 3.0 MPa. Future studies are required to improve the accuracy of identification.