基于压力—速度解耦的深水井筒多相流高精度数值模拟新算法  

New algorithm for high-precision numerical simulation of multiphase flow in deepwater wellbore based on pressure-velocity decoupling

作　　者：娄文强 王志远[3] 孙大林 张剑波 孙小辉 孙宝江[3] LOU Wenqiang;WANG Zhiyuan;SUN Dalin;ZHANG Jianbo;SUN Xiaohui;SUN Baojiang(National Engineering Research Center of Oil&Gas Drilling and Completion Technology//School of Petroleum Engineering,Yangtze University,Wuhan,Hubei 430100,China;Hubei Key Laboratory of Drilling and Production Engineering for Oil and Gas,Wuhan,Hubei 430100,China;School of Petroleum Engineering,China University of Petroleum(East China),Qingdao,Shandong 266580,China;College of Computer Science and Technology,China University of Petroleum(East China),Qingdao,Shandong 266580,China)

机构地区：[1]油气钻完井技术国家工程研究中心·长江大学石油工程学院 [2]油气钻采工程湖北省重点实验室 [3]中国石油大学(华东)石油工程学院 [4]中国石油大学(华东)计算机科学与技术学院

出　　处：《天然气工业》2024年第2期132-144,共13页Natural Gas Industry

基　　金：国家自然科学基金基础科学中心项目“超深特深层油气钻采流动调控”(编号:52288101);国家自然科学基金青年基金“深海多气合采井筒中水合物流动障碍形成机制与实时监测方法研究”(编号:52304016);“海域天然气水合物水平井开采井筒—地层交界面弱化与失稳机理”(编号:52104056);山东省重大科技创新工程项目“深水复杂钻井多相流动模拟关键技术与监测装备”(编号:2022CXGC020407);山东省自然科学基金项目“基于井筒—储层耦合的海域水合物水平井开采井眼界面弱化失稳机理研究”(编号:ZR2021QE155);油气钻采工程湖北省重点实验室开放课题“救援井压井多相流动时空演化机制与参数优化设计方法”(编号:YQZC202301)。

摘　　要：深水钻完井过程中,受海水及海底地质条件复杂影响,井筒压力控制精度要求高、控制难度大。高精度、高稳定性的深水井筒多相流动模拟器成为解决井筒压力精细化控制的关键。为解决深水井筒高动态流动系统的预测难题,针对深水井筒多相流动漂移流模型,将对流迎风分裂方法(AUSMV)的通量分裂方法与交错网格技术进行融合,优化了压力—密度解耦的高刚度问题,形成了压力—速度解耦的数值算法,并利用二阶优化守恒律的单调迎风—中心方案(OMUSCL2)空间重构+两步龙格库塔时间重构技术提升了数值算法的精度,最后建立了深水井筒多相流高精度数值求解算法,并验证了数值算法的精度与性能。研究结果表明:(1)与常规AUSMV算法相比,新算法具有较低的数值耗散,间断物理信息捕捉能力强,对井筒内气液两相前缘位置的识别度更高;(2)与注气量10×10^(4)m^(3)/d和15×10^(4)m^(3)/d井喷实验对比,新算法模拟井底压力的平均误差分别为1.79%和1.86%;(3)新算法在井口气体剧烈膨胀、超音速流动模拟方面表现出了良好的稳定性和鲁棒性。结论认为,该新算法不仅提升了常规数值算法的精度,同时可为复杂高动态流动系统的井筒压力调控提供有效的技术支撑,有助于提高我国深水井筒压力控制的理论水平,保障深水油气的有效开发。In the process of deepwater well drilling and completion,the complex sea water and seabed geological conditions require highprecision wellbore pressure control and increase the control difficulty.The high-precision and high-stability multiphase flow simulator of deepwater wellbore has become the key to realize the fine control of wellbore pressure.In order to address the difficulty in predicting the high dynamic flow system in deepwater wellbore,aiming at the drift flow model of multiphase flow in deepwater wellbore,this paper integrates the flux splitting method of advection upstream splitting method(AUSMV) with the staggered grid technology,optimizes the high stiffness of pressure-density decoupling,and hence forms a numerical algorithm of pressure-velocity decoupling.Then,the precision of the numerical algorithm is improved using OMUSCL2 space reconstruction + two-step Runge-Kutta time reconstruction technology.Finally,a high-precision numerical algorithm for multiphase flow in deepwater wellbore is established,and its precision and performance are verified.And the following research results are obtained.First,compared with the conventional AUSMV algorithm,the new algorithm has lower numerical dissipation,stronger ability to capture discontinuous physical information,and higher position recognition degree of gas-liquid two-phase leading edge in the wellbore.Second,compared with the blowout experiments with gas injection rate of 10×10^(4) m^(3)/d and 15×10^(4) m^(3)/d,the average error of the bottom hole pressure simulated by the new algorithm is 1.79% and 1.86%,respectively.Third,the new algorithm shows good stability and robustness in simulating the intense expansion of wellhead gas and the supersonic flow.In conclusion,the new algorithm not only improves the precision of conventional numerical algorithm,but also provides effective technical support for wellbore pressure control of the complex high dynamic flow system,which is conducive to improving the theoretical level of deepwater wellbore pressure contr

关 键 词：深水 多相流 压力—速度解耦 OMUSCL2 AUSMV 交错网格 

分 类 号：O359[理学—流体力学] TE5[理学—力学]