不同流变模式下的泡沫钻井压降模型对比与改进

A Comparative Study and Improvement of Pressure-drop Models for Foam Drilling under Different Rheological Modes

泡沫钻井的压降计算是确定合理气液注入量的基础,对泡沫钻井水力压降的研究不少,但是相对于常规钻井水力压降计算,目前泡沫钻井还没有一致认可的计算模型.因此从泡沫流变模式入手,对具有代表性的4种压降模型进行对比,并利用欠平衡水力模拟系统对不同情况下的泡沫压降进行模拟,对比分析结果显示在70％～90％泡沫质量范围内,泡沫流变模式大多与幂律流变模式类似,并且考虑滑脱后的计算结果更加可靠.

Pressure-drop calculation of foam drilling was a basis for reasonably determining the amount of the gas-liquid injection,the study of hydraulic pressure drop in foam drilling was not less,but there were no recognized models for calculating the hydraulic pressure drop corresponding to the conventional drilling.Therefore,starting from the foams rheological modes,four representative models of pressure drop were compared,a underbalanced hydraulic simulation system was used to simulate foam pressure drop under different circumstances.The results show that within the range of 70%to 90%of foam quality,its rheological modes are highly similar to the power law fluid.The results after the slip effect is considered are more reliable.