水力喷射径向钻孔器的流场特性

Study on flow field characteristics of hydraulic jet radial drill

贾建超 廖华林 于怀彬 张涛 李玉梅4

中国石油华北油田公司开发事业部，河北 任丘 062552 中国石油大学（华东）石油工程学院，山东 青岛 266000 中国石油集团渤海钻探工程有限公司工程技术研究院，天津 300457 北京信息科技大学高动态导航技术北京市重点实验室，北京 10010

Development Department of Huabei Oilfield Company, PetroChina, Renqiu 062552, China College of Petroleum Engineering, China University of Petroleum, Qingdao 266000, China Engineering Technology Research Institute, Bohai Drilling Engineering Co., Ltd., CNPC, Tianjin 300457, China Beijing Key Laboratory of High Dynamic Navigation Technology, University of Beijing Information Science & Technology, Beijing 100101, China

水力喷射径向钻孔器的结构优化设计和破岩性能直接决定了钻进速度。文中利用CFX软件建立水力喷射径向钻孔器的有限元数值模型，开展了钻孔器内外流场的三维流动特性分析，研究了入口排量、井眼内径对流场特性的影响规律。结果表明：随着入口排量的增加，前、后喷孔的最大流速均有所增加，且后喷孔的最大流速大于前喷孔；随着井眼内径和入口排量的增加，钻孔器最大流速增大。同时开展的水力喷射钻水泥环实验研究发现，岩样硬度对钻水泥环的喷射效果有较大影响。若岩样硬度较大，形成的水眼较浅；若岩样硬度较小，喷射速度快，易于破岩，形成的水眼较深。研究成果可为优化钻孔器的结构参数、提高钻孔器的工作性能以及完善水力喷射径向钻孔工艺提供理论指导。

The structural optimization design and rock breaking performance of the hydro-jet drill directly determine the drilling speed. In this article, the finite element numerical model of the hydro-jet drill was established by CFX, and the three-dimensional flow characteristics of the internal and external flow fields of the jet drill were analyzed. The effects of inlet displacement and inner wellbore diameter parameters on flow field characteristics were studied for different models and parameters. It is found that as the inlet flow rate increases, the injection speeds of the front nozzle and the rear nozzle increase, and the injection speed of the rear nozzle is greater than the injection speed of the front nozzle; the larger the inner diameter of the wellbore, the larger the flow velocity at the nozzle of the driller; the larger the inlet flow rate, the greater the flow velocity at the nozzle of the driller. At the same time, the hydraulic injection experimental research was carried out. It is found that the hardness of the rock sample has a great influence on the effect of hydraulic injection. The larger the hardness of the rock sample is, the shallower the water eye jet is. If the hardness of rock is small, the jet speed is fast, and it is easy to break the rock and form the deeper water hole. The research results can provide theoretical guidance for the optimization of the structural parameters of the drill, the improvement of the working performance of the drill and the perfection of the radial drilling process.

10.6056/dkyqt202001025