随钻测井仪流道转换器优化设计与数值分析

Optimization Design and Numerical Analysis of Flow Passage Converters in LWD Tools

药晓江 卢华涛 尚捷 王清华 李洋

YAO Xiaojiang LU Huatao SHANG Jie WANG Qinghua LI Yang

中海油田服务股份有限公司，河北三河 065201 纽美瑞克（北京）软件有限责任公司，北京 100080

CNOOC Oilfield Services Limited, Sanhe, Hebei, 065201, China NUMECA (Beijing) Software Limited, Beijing, 100080, China

随钻测井仪流道转换器流道截面设计不合理，不仅会造成随钻测井仪器内流道局部流场紊乱，致使仪器局部冲刷严重，造成仪器使用寿命缩短；还会导致仪器压力损失偏高，影响仪器的适用性。为此，采用CFD方法，对某型随钻测井仪流道转换器进行优化设计，并对4种设计方案进行了全三维数值模拟和对比，认为影响流道转换器流场性能的主要因素是扩张角和内流道截面积的连续性。最优设计方案的扩张角较小，内流道截面积连续，轴向速度下降更平缓，总压损失最小，流场流速分布更均匀。试验结果表明，流道转换器扩张角、内流道截面积不连续性与流道转换器流场分布均匀性呈负相关，与压力损失呈正相关；总压损失系数理论值与试验值对应的差值不大于0.076%，且变化趋势均与理论分析结果相同。研究结果为流道转换器的优化设计提供了理论依据。

Improper design of flow passage converter section in LWD ( logging while drilling) tools can cause local flow-field turbulence and result in serious local erosion of the tool, thus reducing its service life. It can also lead to large pressure loss of the tool and affect its applicability. For this reason, CFD (computational fluid dynamics) method was applied for the optimization design of a certain type of flow passage converter in an LWD tool. According to the full 3D numerical simulation and comparison of four design schemes, the main factors affecting the flow-field performance of the flow passage converter were thought to be the expansion angle and the continuity of the cross-sectional area of the internal flow passage. The optimal design has a smaller expansion angle, a more continuous cross-sectional area of the internal flow passage, a gentler decline in axial velocity, a minimum total pressure loss, and a more uniform flow velocity distribution in the flow field. The research results showed that the expansion angle and the discontinuity of the cross-sectional area of the internal flow passage were negatively associated with the uniformity of the flow field distribution in the flow passage converter and positively with the pressure loss. The difference between theoretical and experimental total pressure loss coefficients was not more than 0.076%, and the change trend was the same as the result of theoretical analysis. The research results can effectively serve as a theoretical basis for the optimization design of flow passage converters.

国家重点研发计划项目“深海关键技术与装备”子课题“大直径旋转导向钻井系统装备研制与示范作业”（编号：2017YFC0307100）部分研究内容

https://doi.org/10.11911/syztjs.2021069