径向井远端压裂产能计算模型及应用

Productivity calculation of radial well distal fracturing and its application

考虑到近端裸眼段井筒中流体的流动为变质量流动,基于质量守恒定律、动量定理、微元线汇理论推导了径向井近端裸眼段井筒内管流模型,基于复位势理论、镜像反映原理推导了油藏中流体渗流模型,进而推导出考虑井筒压降的径向井近端裸眼段产能计算模型,并建立径向井远端压裂段的产能计算模型。通过实例计算研究径向井近端裸眼段沿井筒径向流量分布以及径向井远端压裂产能情况。研究结果表明:沿近端裸眼段井筒径向流量分布图呈现凹槽状,在近段裸眼段跟端和趾端附近径向流入量较大,中间部位流量较小,而且较为平均;压裂产能的计算精度较高。

Considering the radial wellbore fluid flow was variable mass flow, based on the law of conservation of mass, momentum theorem and the theory of infinitesimal line congruence, the radial wellbore flow model was derived. Based on the complex potential theory and the mirror image principle, the fluid percolation model in the reservoir was derived. And then productivity calculation model considering wellbore pressure drop was derived, and productivity calculation model of distal radial shaft fracture was derived. The flux distribution of radial well and productivity through example calculation was also studied. The results show that the flux distribution diagram of radial well is groove-shaped, the flux distribution is large at the heel side and the toe side, while the middle is small and average; productivity calculation of radial well distal fracturing has higher calculation accuracy.