摘要
利用环空流速分布规律和边界层绕流理论,探讨水平井大斜度和水平井段钻进时钻井液冲蚀岩屑床的临界流速。水平井大斜度和水平井段钻进时,环空岩屑因停泵而自然沉降形成岩屑床,通过对岩屑床表面颗粒进行受力分析和边界层绕流假设,结合数学推导得到床面岩屑颗粒所受钻井液表面切力解析式,建立床面颗粒临界启动解析模型。模型计算与实验数据结果表明,在不同井斜角和颗粒直径条件下,循环介质为清水时模型预测的临界启动流速与实验数据的绝对平均误差不超过8.80%,循环介质为PAC溶液时绝对平均误差在2.51%～7.06%。边界层绕流和环空流速是岩屑临界启动流速的重要影响因素。
The incipient velocity of drilling fluid eroding cuttings bed during horizontal well inclination and horizontal well drilling is discussed on the basis of distribution law of annulus velocity and the theory of boundary layer. After the horizontal well section is drilled, the cuttings in annulus are naturally settled and a cuttings bed is formed due to pump stoppage. Through the force analysis of the cuttings bed surface particles and the assumption of the boundary layer flow, combined with mathematical derivation, the cuttings on the surface of the cuttings bed are subjected to the analytical formula of the surface shear of the drilling fluid, and an analytical model for the critical incipient velocity of the cuttings bed surface is established. The model calculation and experimental data show that, under different inclination angles and particle sizes, the absolute average error of the critical incipient velocity predicted by the model is less than 8.80%,and when the circulating medium is PAC solution, the absolute average error of the critical incipient velocity is in the range of 2.51%~7.06%. It is obvious that the boundary layer flow and the annulus velocity distribution are important factors influencing the critical incipient velocity of the cuttings.
作者
孙晓峰
汤捷
袁玉金
张克博
陈烨
胡乔波
SUN Xiaofeng;TANG Jie;YUAN Yujin;ZHANG Kebo;CHEN Ye;HU Qiaobo(Northeast Petroleum University,Daqing 163318,China;PetroChina International Latin America,Rio de Haneiro 999074,Brazil)
出处
《成都理工大学学报（自然科学版）》
CAS
CSCD
北大核心
2019年第2期204-211,共8页
Journal of Chengdu University of Technology: Science & Technology Edition
基金
国家科技重大专项(2017ZX05009-003)
国家自然科学基金项目(51674087
51474073)
关键词
岩屑床
井眼清洁
表面切力
临界启动流速
水平井
cuttings bed
hole-cleaning
surface shear force
critical incipient velocity
horizontal wells
