Abstract:

It is of great practical significance to accurately predict the characteristic parameters of slug flow in gas-liquid two-phase flow. The Renault model is a two-fluid model based on the non-viscous Kelvin-Helmholtz stability criterion and the viscous Kelvin-Helmholtz stability criterion, which can capture the interface movement of the slug front and rear. However, this model uses Riemann precise solution between liquid phase cells and the solution speed is slow. In order to simplify the calculation, the traveling wave method was introduced into the solution process of the liquid phase equation in the Renault model, and the possible dry areas were replaced with thin liquid film, making the traveling wave method applicable to all computing units. Under the condition of ensuring the accuracy of the model, the calculation speed was greatly improved, and the operation time was reduced by 28% on average compared with the Renault model. By comparing the calculation results of this model with the data of indoor small-scale loop experiment, the liquid holding rate is consistent with the measured results. The relative errors of pressure drop and slug length calculation are respectively within 25% and 30%, and the main distribution is within 20%. It shows that the improved transient slug flow model has the characteristics of fast calculation and high calculation accuracy, and has certain engineering application value.

Key words: gas-liquid two-phase flow, model, traveling wave method, slug flow, hydraulic calculation

摘要：

气液两相流中，准确预测段塞流的特征参数具有重要的现实意义。Renault模型是基于非黏性Kelvin-Helmholtz（IKH）稳定性准则与黏性Kelvin-Helmholtz（VKH）稳定性准则建立的能够捕捉段塞前后界面运动的双流体模型，但该模型在液相单元格之间采用Riemann精确解，求解速度较慢。为简化计算，本文将行波法引入到Renault模型的液相方程求解过程，并对可能出现的干区用薄液膜代替，使行波法适用于所有计算单元，在保证模型精度的条件下，极大地提高了计算速度，运算时间相比Renault模型平均减少28%。对比本模型计算结果与室内小型环道实验数据，持液率与实测结果相一致，压降、段塞长度计算相对误差分别在25%、30%以内，且主要分布在20%以内。说明本文改进的瞬态段塞流模型具备运算快速、计算精度较高的特点，具有一定的工程应用价值。

关键词: 气液两相流, 模型, 行波法, 段塞流, 水力计算