In order to deploy CO₂ capture and storage (CCS) systems to mitigate climate change, it is crucial to develop reliable models for design and operational considerations. A key element of the system is the interface between transportation and storage, namely the injection well, where various transient scenarios involving multiphase flow will occur.

In the literature there are very few data relevant for validation of vertical multiphase flow models for CO₂. Hence in this work, we present measurements of liquid holdup, pressure drop and flow regime for upward and downward flow of CO₂ in a pipe of inner diameter 44mm at a pressure of 6.5MPa, a condition relevant for CO₂-injection wells.

The experimental results indicate that the flow is close to no-slip. We have compared the experimental data to predictions by well-known models for phase slip and frictional pressure drop, and the results show that overall, the best model is the simplest one – the fully homogeneous approach, in which no slip is assumed and the friction is calculated simply by employing gas-liquid mixture properties in the single-phase friction model.

为了部署CO ₂捕获和存储（CCS）系统来缓解气候变化，开发可靠的模型以进行设计和操作考虑至关重要。该系统的关键要素是运输和存储之间的接口，即注入井，在此将发生涉及多相流的各种瞬态情况。

在文献中，很少有数据与CO ₂的垂直多相流模型的验证有关。因此，在本工作中，我们持液量，压降的本测量和流态为向上和向下的CO流₂在6.5MPa的，相关的CO的条件的压力在内径44mm的管₂步喷射孔中。

实验结果表明，流量接近无滑移。我们将实验数据与知名模型的相移和摩擦压降预测值进行了比较，结果表明，总体而言，最佳模型是最简单的模型–完全均质的方法，其中不假定滑动和摩擦通过在单相摩擦模型中采用气-液混合特性可以简单地计算出Δε。