上倾管高黏油气两相流型及压降特性

Flow patterns and pressure drop characteristics on high-viscosity oil and gas two-phase flow in upward pipe

利用室内实验装置,对上倾管内高黏油气两相流的流型和压降特性进行了实验研究。实验中观测到7种流型,得到了不同工况下的压力波动信号及压降值。实验结果表明,由于液相黏度的影响,上倾管内大部分流型的过渡边界向流型图的左侧偏移,且黏度越大偏移程度越大。将流型数据与Barnea流型判断模型进行对比,发现在高黏度时两者误差较大。根据压降数据得出,由于高黏度时液滴的附着作用增强,在气液表观速度均较小时,会出现黏度增加而压降却减小的现象。验证了OLGA模型和Zhang模型对于压降的计算精度,发现高黏度时模型的计算误差远大于低黏度情况。通过高黏度闭合关系式对Zhang模型进行修正,结果表明可以显著地提高其计算精度。

Flow patterns and pressure drop characteristics on high-viscosity oil and gas two-phase flow in upward pipe were experimentally studied with an indoor experiment apparatus. Seven flow patterns were observed in the experiment. Pressure fluctuation signals and pressure drop values under different operating conditions were obtained. The results show that, due to the influence of liquid viscosity, the transition boundary of most flow patterns in the upward tube shifts to the left side of the flow pattern diagram, and the larger the viscosity is, the greater the migration degree is.The data of flow patterns were compared with Barnea model, whose error was found to be increased at higher viscosity. According to the pressure drop data, due to the boost of adhesion at higher viscosity,the phenomenon that the pressure drop decreases with the increase of liquid viscosity may occur during the lower superficial velocities. Comparison verification of pressure drop with OLGA model and Zhang model was performed,whose calculation error under high-viscosity was found to be greater than that of low-viscosity. Finally, the Zhang model was modified with the closure relationships for high-viscosity oil and the updated results showed that the accuracy can be significantly improved.