垂直上升气液两相弹状流模型

基于等效弹单元思想,改进了预测垂直上升管中充分发展气液弹状流流动特性的模型。 模型中考虑了界面切应力对液膜运动的影响;并在液弹空隙度预测中引入临界气体夹带速度的概念,以此来描述弹状流中大气泡尾部的混合特性。本文提出的模型还考虑了管径对液弹空隙度的影响。弹状流模型的计算结果得到本文及其他作者实验数据的验证。

HYDRODYNAMIC MODEL OF UPWARD GAS-LIQUID SLUG FLOW IN VERTICAL TUBES

By reducing intermittency to periodicity, the very complex slug flow structure is simplified to an equivalent unit consisting of a liquid slug, one adjacent Taylor bubble and an aerated liquid film. A region with high local concentration of dispersed bubbles is formed in the front of the liquid slug, because the liquid film entrains gas penetrating the liquid slug. In the current paper, a hydrodynamic model is constructed for gas - liquid two - phase slug flow in vertical tubes, which considers the gas exchange between the Taylor bubble and its following liquid slug. It can predict the flow characteristics of this complex flow pattern. A detailed experimental investigation was carried out in air/water system. An EKTAPRO 1000 high speed motion analyzer and the optical probes were used as measuring instruments. The results predicted by this model are in better agreement with the available experimental data.