考虑气液相滑移影响的气井两相节流预测模型研究

Study on Prediction Model for Two-phase Flow Choke in Gas Wells with Slippage Phenomenon Involved

为进一步提高气井井下节流两相流流型判别及质量流量预测的准确性,通过建立气液两相节流模型临界压力比和质量流量预测评价方法,对3个常用的气液两相节流模型进行了评价。从质量、动量及能量守恒原理出发,运用对比拟合的方法同时考虑节流过程气液相滑移的影响,提出了新的气液两相井下节流流型判别准则。在此基础上提出了适应于临界流/亚临界流条件下节流质量流量预测的新模型,并运用新模型预测了临界压力比及节流质量流量。在实验数据范围内,该模型的预测性能明显优于已有模型。

In order to further improve accuracy of gas well downhole choke two-phase flow state discrimination and mass flow rate prediction, by establishing the method to predict and evaluate the critical pressure ratio and mass flow rate of throttle model of gas-liquid two-phase,three conventional two-phase choke models were evaluated. Based on mass, momentum and energy balance,using the method of comparison and fitting and considering the influence of slip between gas and liquid, a new criterion was presented. On this basis, a new model is proposed to predict the mass flow rate of critieal/subcritical flow. Using the new model to predict the critica/pressure ratio, mass flow rate, within the scope of the experimental data, the new model has higher prediction accuracy than the other three conventional models.