三面加热窄矩形通道内气液两相流流型研究

以去离子水为工质，对截面为3 mm×43 mm的三面加热窄矩形通道内流型转化过程进行可视化实验研究。借助高速摄影仪记录可视化数据，观察到泡状流、弹状流、搅拌流和气膜塞状流等4种主要流型，并详细描述了各种流型发生时通道内气泡转化的过程。记录不同流型转化时的临界点，绘制出三面加热窄矩形通道的流型图，分析流型图中流型转化边界曲线的趋势及形成机理。将本实验流型图与现有相似通道尺寸流型图进行对比，结果表明：三面加热条件下的流型转化过程与绝热条件下的空气 水流型转化过程差异很大，某些流型转化曲线存在趋势上的不同；由于窄边加热部分的影响，与单面加热通道的流型转化过程也存在明显差异。气膜塞状流在绝热条件和单面加热条件下均未出现。

Study of Gas-liquid Two-phase Flow Pattern in Three-side Heating Narrow Rectangular Channel

Taking deionized-water as working fluid, the flow pattern transformation process in a three-side heating narrow rectangular channel with a 3 mm×43 mm cross section was studied with visualization experiment. A high speed camera was used to record visualization data. Four main flow patterns, bubble flow, slug flow, stirring flow and gas film plug flow, were observed, and the transformation process of bubble forms inside channels of various flow patterns was recorded in detail. The critical point of the flow pattern transformation was recorded and the flow patterns of three-side heating narrow rectangular channel were drawn. The trend and formation mechanism of the boundary curves of flow pattern transformation in flow pattern map were analyzed. Compared with the existing flow patterns of similar channel size, it shows that the flow pattern transformation process and the trend of some flow pattern transformation curves are very different between the three-side heating flows and the adiabatic air-water flows. Due to the effect of narrow-side heating section, the flow pattern transformation process is also significantly different from that in single-side heating channel. The gas film slug flow does not appear either under the adiabatic or the single-side heating conditions.