Influence of slug flow on flow fields in a gas-liquid cylindrical cyclone separator: A simulation study

doi:10.1016/j.cjche.2020.03.026

Abstract

Abstract: A simulation method for slug flow based on the VOF multiphase flow model was implemented in ANSYS^® Fluent via a user-defined function (UDF) and applied to the dissipation of liquid slugs in the inlet pipe of a gas-liquid cylindrical cyclone (GLCC) separator while varying the expanding diameter ratio and angle of inclination. The dissipation of liquid slug in inlet pipe is analyzed under different expanding diameter ratios and inclination angles. In the inlet pipe, it is found that increasing expanding diameter ratio and inclination angle can reduce the liquid slug stability and enhancing the effect of gravity, which is beneficial to slug flow dissipation. In the cylinder, increasing the expanding diameter ratio can significantly reduce the liquid carrying depth of the gas phase but result in a slightly increase of the gas content in the liquid phase space. Moreover, increasing the inclination angle results in a decrease in the carrying depth of liquid in the vapor phase, but enhances gas-liquid mixing and increases the gas-carrying depth in the liquid phase. Taking into consideration the dual effects of slug dissipation in the inlet pipe and carrying capacity of gas/liquid spaces in the cylinder, the optimal expanding diameter ratio and inclination angle values can be determined.

Key words: GLCC, Slug simulation, Flow pattern, Liquid slug dissipation, Cyclonic flow field analysis

摘要： A simulation method for slug flow based on the VOF multiphase flow model was implemented in ANSYS^® Fluent via a user-defined function (UDF) and applied to the dissipation of liquid slugs in the inlet pipe of a gas-liquid cylindrical cyclone (GLCC) separator while varying the expanding diameter ratio and angle of inclination. The dissipation of liquid slug in inlet pipe is analyzed under different expanding diameter ratios and inclination angles. In the inlet pipe, it is found that increasing expanding diameter ratio and inclination angle can reduce the liquid slug stability and enhancing the effect of gravity, which is beneficial to slug flow dissipation. In the cylinder, increasing the expanding diameter ratio can significantly reduce the liquid carrying depth of the gas phase but result in a slightly increase of the gas content in the liquid phase space. Moreover, increasing the inclination angle results in a decrease in the carrying depth of liquid in the vapor phase, but enhances gas-liquid mixing and increases the gas-carrying depth in the liquid phase. Taking into consideration the dual effects of slug dissipation in the inlet pipe and carrying capacity of gas/liquid spaces in the cylinder, the optimal expanding diameter ratio and inclination angle values can be determined.

关键词: GLCC, Slug simulation, Flow pattern, Liquid slug dissipation, Cyclonic flow field analysis

Xiaoming Luo, Jing Ren, Tong Chen, Yibin Wang, Yuling Lü, Limin He. Influence of slug flow on flow fields in a gas-liquid cylindrical cyclone separator: A simulation study[J]. Chinese Journal of Chemical Engineering, 2020, 28(8): 2075-2083.

Xiaoming Luo, Jing Ren, Tong Chen, Yibin Wang, Yuling Lü, Limin He. Influence of slug flow on flow fields in a gas-liquid cylindrical cyclone separator: A simulation study[J]. 中国化学工程学报, 2020, 28(8): 2075-2083.

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