摘要
针对水基微泡沫钻井液壁面滑移现象,提出了一种考虑壁面滑移的水基微泡沫钻井液流变性能校正方法。采用六速旋转黏度计,对不同内外筒间隙条件下微泡沫钻井液的流变性能进行测试,再利用Tikhonov正则法校正实验数据,得到考虑壁面滑移效应的水基微泡沫钻井液流变曲线和滑移速度。结果表明,当剪切应力大于某一个临界值后,滑移速度不为零,且随着剪切应力的增大而增大,此时则认为发生了壁面滑移;采用文章中讨论的方法和API方法得到的流变参数之间有显著差异,滑移校正前后τy变化较小,但K值在校正后显著减小,而n值在校正后显著增大,表明API方法对水基微泡沫钻井液屈服值的计算较准确,但对微泡沫钻井液n、K值的计算应考虑壁面滑移的影响。
In view of the wall slip phenomenon of water based micro foam drilling fluids,this paper develops a rheological property correction method considering the wall slip effect.The six-speed rotary viscometer was used to test the rheological properties of the drilling fluid system under different internal-external cylinder clearance conditions and Tikhonov regularization method was used to correct the experimental data to finally obtain the flow curve and slip velocity of water based micro foam drilling fluids,considering the wall slip effect.Comparison of the pre-and post-correction experimental results shows that when the shear stress exceeds a certain threshold,the slip velocity,no longer close to zero,grows with the further increase of the shear stress,and it is considered that wall slip occurs.Considerable differences are observed between the rheological parameters based on API and proposed methods—a minor difference is found inτy,and yet the K value declines and n value grows greatly after correction.It is indicated that the API method can accurately calculate the yield stress of water based micro foam drilling fluid,while the calculation of the n and K values shall incorporate the wall slip effect.
作者
陆海瑛
冯巍
赵俊
任涛
王贵
LU Haiying;FENG Wei;ZHAO Jun;REN Tao;WANG Gui(PetroChina Tarim Oilfield Company,Korla 841000,Xinjiang,China;Southwest Petroleum University,Chengdu 610500,Sichuan,China)
出处
《新疆石油天然气》
CAS
2021年第4期8-14,共7页
Xinjiang Oil & Gas
关键词
水基微泡沫
钻井液
壁面滑移
滑移速度
正则化
water based micro foam
drilling fluid
wall slip
slip velocity
regularization
