水平井不同产能计算方法探讨

Discussion on  different calculation methods of productivity for horizontal well

罗远儒 2 陈勉¹ 金衍¹ 李发照² 侯静³ 杜明翰³

1．中国石油大学（北京）石油天然气工程学院，北京102249 中国石化中原油田分公司采油一厂，河南 濮阳 457171 中国石油长城钻探工程有限公司员工培训管理中心，北京 100101

College of Petroleum Engineering, China University of Petroleum, Beijing 102249, China No.1 Oil Production Plant, Zhongyuan Oilfield Company, SINOPEC, Puyang 457171, China Employee Training Management Center, Great Wall Drilling Engineering Company, CNPC, Beijing 100101, China

采用解析式计算产能时，由于其在推导过程中叠加误差的存在，导致计算结果偏差较大。常规耦合产能计算方法准确性虽好，但对低渗透油藏并没有考虑启动压差的影响，适用面较窄。文中在油藏渗透率较低时，考虑了非达西渗流及启动压力的影响，运用势的叠加原理和镜像反映计算油藏与水平井筒渗流耦合条件下的水平井产能；综合考虑了非达西效应、启动压力、非均质性、井筒摩擦、加速度和重力影响等因素。通过与国内外常用的6种解析计算方法进行对比分析可知，采用耦合模型的计算结果与水平井实际产能相对误差较小。因此，考虑了低渗透效应的耦合产能预测模型计算结果更加接近油井的真实产量，适用面更广。

When the productivity is calculated by analytical productivity formulae, the results have some deviations due to the superposition errors in the process of deduction. Though the accuracy of calculation method for conventional coupling productivity is high, its application range is not wide because the non-Darcy flow and the influence of start-up pressure difference are not considered. This paper considers the non-Darcy flow and the influence of start-up pressure difference and uses the potential superposition principle and mirror image principle to calculate the horizontal well productivity at the condition of coupling wellbore and reservoir when the reservoir permeability is low. It also considers some complicated factors, such as non-Darcy effect, start-up pressure, heterogeneity, fluid friction loss, the change of acceleration and gravity. Comparing with the results of the six productivity formulae at home and abroad, it is shown that the relative error is small between the practical and the calculated value. Therefore, the calculated results based on the model which considers the coupling productivity prediction at low permeability effect are closer to the actual production rate, having a wide application range.

10.6056/dkyqt201201022