Abstract Venturi is one of the most commonly used flowmeters for measuring gas-liquid flow at the natural gas wellhead. A better understanding of the flow mechanism and the causes for pressure drop is necessary for the establishment of the measurement model. In this study, a one-dimensional pressure drop model between the two pressure taps of Venturi has been proposed for vertical annular-mist flow. The relations between the liquid film, entrainment rate, void fraction, and velocity slip have been revealed when the annular flow went through Venturi. We consider the gas acceleration in the throat of Venturi. The proportions of various pressure drops are given. The experimental results show that the relative errors of the pressure drop have a confidence probability of 98.5% within 10%. The predicted results are also in good agreement with the on-site data. It proves that the new pressure drop model has good performance.

中文翻译：

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垂直文丘里环流的压降模型

摘要 文丘里流量计是天然气井口气液流量测量最常用的流量计之一。更好地了解流动机制和压降的原因对于建立测量模型是必要的。在这项研究中，文丘里管的两个测压口之间的一维压降模型已被提出用于垂直环形雾流。当环形流通过文丘里管时，已经揭示了液膜、夹带率、空隙率和速度滑移之间的关系。我们考虑文丘里管喉部的气体加速。给出了各种压降的比例。实验结果表明，压降的相对误差在10%以内的置信概率为98.5%。预测结果也与现场数据吻合较好。证明新的压降模型具有良好的性能。