中文摘要：

毛细管精馏是一种分离共沸物系的新型分离技术,它利用毛细管的固-液相互作用来改变液体混合物的汽液平衡。毛细管通道内的气液两相流型在低气速时以泰勒流为主,今使用计算流体力学方法,对毛细管内泰勒流的多种影响因素,如：壁面作用、气液速率以及流体物性等进行了研究。首先考察壁面作用的影响,发现壁面粗糙度能改变气液柱形状和流场,粗糙度增大使通道内气液两相流型由泰勒流向泡状流转变,流动状态由层流向涡流转变。模拟不同接触角下的气液流动,发现壁面吸附作用在一定程度上影响气液柱长度和气液界面间的形状。通过模拟不同气液速率下的气液流动,观察气液柱长度与气液速率之间的关系。对模拟气液柱长度进行量纲分析,得到了泰勒流的气液柱长度的关联式,将该式与文献测定值进行比较,发现在一定范围内吻合较好。

英文摘要：

Capillary distillation is a new technology mainly used for the separation of the binary azeotropic liquid mixtures. It utilizes the solid-liquid interfacial forces to change vapor-liquid equilibrium inside the capillary porous media. Under low gas velocity, the flow pattern in a capillary channel is typically the so-called Taylor flow regime. A computational fluid dynamics package FLUENT was adopted for simulation of the effects including wall function, fluid velocities and physical properties on gas-liquid two-phase Taylor flow in a Y-junction capillary. Firstly, wall roughness was found to be able to change the shape of slugs and flow field in the capillary. With the increase of wall roughness, gas-liquid two-phase flow regimes in the capillary change from Taylor flow into bubble flow, and the flow field from laminar flow into turbulent flow. Then by calculating gas-liquid flow under various contact angles, it can be found that wall surface adhesion can affect slug length and the shape of gas-liquid interface to a certain degree. Meanwhile, by calculating gas-liquid two phases flow under various gas and liquid velocities, the relationship between slug length and gas/liquid superficial velocities was obtained. Finally, using dimensional analysis and regression calculation to deal with gas and liquid slug lengths of the Taylor flow, a correlation was developed, which has a good agreement with the experimental data from the literature in a wide range.