Abstract: The accuracy of CFD simulation results for bubble columns depends on closure models, such as interphase force models and turbulence models. Most of the previous reports were for empty column without internals, and currently, there is a lack of studies related to bubble column with internals. This study examined the effects of six commonly used turbulence models (Standard k-ε, RNG k-ε, Realizable k-ε, Standard k-ω, SST k-ω, and RSM) on the hydrodynamics in the pilot-scale bubble columns without internals and with tube bundles. The results showed that the RSM predicted significantly higher for turbulent kinetic energy, turbulent dissipation rate, and turbulent viscosity in the empty column compared to eddy viscosity models (k-ε and k-ω models). However, this difference was considerably reduced in the bubble column with tube bundles, and the tube bundles significantly suppressed the turbulence intensity in the liquid phase. Meanwhile, by comparing the simulated gas holdup and axial liquid velocity values with experimental data, it was found that the eddy viscosity models accurately predicted the gas holdup in the central region of the empty column, while the RSM accurately predicted the gas holdup in all regions except the central region. However, the radial distribution of gas holdup predicted by six turbulence models in the bubble column with tube bundles was almost identical, with accurately predicting the gas holdup only in the 0.5<r/R<0.7 region. The Realizable k-ε model's predictions of axial liquid velocity in both empty column and the bubble columns with tube bundles were in good agreement with experimental data, significantly outperforming other turbulence models. Therefore, it was recommended to use the Realizable k-ε model for future simulations of hydrodynamics in bubble columns.

Key words: bubble column, internal tube bundles, two-phase flow, computational fluid dynamics, turbulence model

摘要： 含列管束鼓泡塔的CFD模拟结果准确性与相间作用力模型、湍流模型等封闭模型有关。本工作考察了常用的6种湍流模型(标准k-ε、RNG k-ε、Realizable k-ε、标准k-ω、SST k-ω和RSM)对不含内构件及含列管束的中试规模鼓泡塔内流体动力学的影响。结果表明，RSM预测的空塔内流体的湍流动能、湍流耗散率和湍流黏度均远高于涡黏模型(k-ε模型、k-ω模型)，但在模拟列管塔时这种差距明显缩小，而且列管显著抑制了液相的湍动程度。同时，将鼓泡塔内气含率及轴向液速的模拟值与实验测量数据进行了对比，发现涡黏模型仅可准确预测空塔内中心区域气含率而RSM可预测其余区域气含率，6种湍流模型预测的列管塔内气含率径向分布几乎一致；Realizable k-ε模型预测的空塔及列管塔内轴向液速值与实验数据高度吻合，明显优于其他湍流模型，在模拟鼓泡塔内流体力学时推荐使用。

关键词: 鼓泡塔, 列管内构件, 两相流, 计算流体力学, 湍流模型