气体钻井发电机涡轮设计与性能试验

Generator Turbine Design and Performance Test of Gas Drilling

近年,电磁波和微波随钻测量传输技术被应用于气体钻井井眼轨迹的测量与控制,但由于电池供电功率较低,无法满足大于3000 m井深的随钻测控需求,井下发电机技术可有效提高传输功率,只是气体密度低且可压缩,涡轮和导轮构成的常规组件无法驱动井下发电机正常运转。文章在研究了二维流场中涡轮叶片的速度矢量三角形基础上,结合气体钻井工况分析了涡轮的输出转速、扭矩关系,提出借助行星轮机构提高涡轮输出抗扭特性的设计思路,设计出适用于气体钻井的井下发电机驱动涡轮,使发电机在负载改变时依然可维持稳定输出,并运用计算流体动力学软件(CFD)对涡轮进行全三维流场仿真模拟,通过测试装置验证了发电机的输出效果。结果表明:发电机稳态输出功率可达500 W,满足气体钻井随钻测量传输电磁波和微波传输的大功率需求。

In recent years,electromagnetic wave and microwave transmission techniques have been applied to the measurement and control of gas drilling borehole trajectories.But due to the low power supply of the battery,it cannot meet the requirements of measurement and control while drilling for wells with a depth greater than 3000 m.Downhole generator technology can effectively improve the transmission power,but the conventional assembly consisting of a turbine and guide wheel cannot drive the downhole generator properly due to the low density and compressibility of the gas.In this paper,based on the study of the velocity vector triangle of turbine blades in two-dimensional flow field,the output speed and torque relationship of turbine were analyzed in the context of gas drilling conditions,and the design idea of improving the torsional resistance of turbine output with the help of planetary gear mechanism was proposed to design a downhole generator driving turbine suitable for gas drilling,so that the generator can maintain stable output when the load changes.In addition,CFD software was used to simulate the full three-dimensional flow field of the turbine,and the output of the generator was then tested in a test rig.The test results showed that the steady-state output of the generator can reach 500 watts,which meets the high power requirements for the transmission of electromagnetic waves and microwave for gas drilling.