射孔相位对水平井筒变质量流压降影响规律

EFFECT LAWS OF THE PERFORATION PHASES ON THE PRESSURE DROP OF VARIABLE MASS FLOW IN HORIZONTAL WELLBORE

根据相似原理设计的小尺寸水平井简模拟实验井段不能够同时实现几何相似、运动相似和动力相似，所以小尺寸模拟实验井段与水平井筒实际生产情况存在一定偏差。为了能够真实地反映水平井筒实际生产情况，实验采用外径139．7mm壁面打孔套管模拟射孔完井水平井筒，设计了3种射孔相位角，主流雷诺数为1000～20000，壁面注入比为0．01％～10％。实验研究了射孔相位角对壁面摩擦压降、混合压降、总压降的影响规律，同时分析了壁面注入比对混合压降和加速度压降的影响规律。研究结果表明：随着射孔相位角增大，壁面摩擦压降和总压降增大，混合压降减小；随着壁面注入比的增加，混合压降和加速度压降均增加。

Since the simulated experimental well sections of small-size horizontal wellbore designed by similarity principle cannot affect the simultaneous realization of geometric similarity, kinematic similarity and dynamic similar- ity, there is a deviation between the simulation and actual production scenario. In order to actually reflect the prac- tical performances of the horizontal borehole production＇ a wall-ported casing with 139.7 mm external diameter is a- dopted to simulate the production. Three kinds of perforation phase are designed with the main-stream Reynolds number of 1 000- 20 000 and the wall injection-ratio of 0.01% -10%. The influencing laws of the perforation phases on the wall frictional pressure drop, mixed pressure drop and total pressure drop are researched in the exper- iment. In the meantime, the influencing laws of the wall injection on the mixed pressure drop and acceleration pres- sure drop are analyzed. The experiment results indicate that the wall frictional and total pressure drops rise as a re- sult of the increased perforation phase angle, while the mixed pressure drop reduces ; and along with the increase of the wall injection ratio, the mixed pressure drop and acceleration pressure drop increase as well.