孔板通气气液两相流动特性研究

采用实验与数值模拟相结合的方法研究了孔板通气气液两相流动特性和气层形成机理.应用高速录像观察了通气气液两相流流动形态，采用Level Set方法和RNG k-ε湍流模型对通气平板流场进行了数值计算.结果表明气层覆盖区域压力是判定气层形成的重要参数:泡间高压消失表明当地的气泡开始形成气层，当气层基本形成时，壁面压力趋于一致.旋涡结构在气层形成不同阶段具有明显的特征，在气层初始形成位置前后，肾形涡由于气泡接触相互作用而逐渐消失；在气层完全形成位置前后，旋涡结构重新生成.随着孔间距的增加，气层形成位置由于横向距离增加而向下游移动，但相互作用区域变化不大. 

Analysis on Gas-Liquid Two-Phase Flows Characteristics Around a Plane

Combining experiment and numerical simulation, the gas-liquid two-phase flow characteristics of plane were studied in this paper. Ventilated two-phase flows phenomenon was observed by a high-speed photograph, and its flow field was simulated by using the Level Set method and RNG k-ε turbulence model. The results show that, the pressure of air layer coverage area is an important parameter to evaluate the formation of air layer:the location that high pressure between bubbles disappears is the initial location of air layer; when the air layer forms, the pressure tends to be consistent. Vortex structure has different characteristics during the air layer forming process. During the initial location kidney-shaped vortexes disappear gradually. When the air layer is formed, the vortexes regenerate. With the increase of space between pores, the forming locations of air layer move downstream due to transverse distance increases, but the interaction region changes little.