深层页岩欠平衡钻井气液固三相瞬态流动传热模型研究

Research on a Transient Flow Heat Transfer Model of Gas-Liquid-Solid Three-Phase Flow for Unbalanced Drilling in Deep Shale Wells

张文平 许争鸣 吕泽昊 赵雯

ZHANG Wenping XU Zhengming LYU Zehao ZHAO Wen

中石化石油工程技术研究院有限公司，北京 102206 中国地质大学（北京）能源学院，北京 100083 中国石油油气和新能源分公司，北京 100007 中国石油青海油田分公司采气二厂，青海茫崖 816499

Sinopec Research Institute of Petroleum Engineering Co., Ltd., Beijing, 102206, China School of Energy Resources, China University of Geosciences (Beijing), Beijing, 100083, China PetroChina Oil & Gas and New Energy Company, Beijing, 100007, China The No.2 Gas Production Plant, PetroChina Qinghai Oilfield Company, Mangya, Qinghai, 816499, China

井底压力的准确预测和有效控制是深层页岩欠平衡钻井作业的关键，但岩屑及环空流体与周围环境之间的对流换热对传统井底压力计算模型精度的影响较大。为此，建立了瞬态非等温井筒气液固三相流动模型，根据连续性方程和动量守恒方程，计算了流体速度、相体积分数和压力，并求解了不同径向层的能量守恒方程，得到了整个井筒–地层系统的温度分布，并采用迭代法，耦合求解了深度和径向方向上的温度、压力和流体性质；模型计算结果与欠平衡钻井作业的现场数据之间误差小于5.0%，验证了该模型的准确性与可靠性。基于所建立的模型，对比分析了考虑和不考虑岩屑存在及对流换热效应时预测的压力和温度差异，分析了欠平衡压差、机械钻速、地温梯度等因素对井筒压力和温度分布的影响规律。深层页岩欠平衡钻井气液固三相瞬态流动传热模型为控压钻井、欠平衡钻井在深层页岩油气中的高效应用提供了理论支撑。

Accurate prediction and effective control of bottom hole pressure (BHP) are crucial for underbalanced drilling of deep shale wells. However, convective heat transfer in cuttings, annulus fluid, and surrounding environment significantly impacts the accuracy of traditional BHP calculation models. Therefore, a transient non-isothermal flow model of gas, liquid, and solids within the wellbore was developed. Based on the continuity equation and momentum conservation equation, fluid velocity, phase volume fractions, and pressure were calculated. Meanwhile, the energy conservation equation for different radial layers was solved to obtain the temperature distribution of the entire wellbore–formation system. The temperature, pressure, and fluid properties in the depth and radial directions were coupled and solved using an iterative method. The calculated results of this model exhibited an error of less than 5.0% compared with the field data from underbalanced drilling operations, demonstrating its accuracy and reliability. With the proposed model, a comparative analysis was conducted to assess the differences in pressure and temperature predictions when the presence of cuttings and convective heat transfer effects were considered or neglected. The study also analyzed the impact of factors such as underbalanced pressure difference, rate of penetration (ROP), and geothermal gradient on wellbore pressure and temperature distribution. The transient flow heat transfer model of gas, liquid, and solid phases for underbalanced drilling in deep shale wells provides theoretical support for the efficient application of managed pressure drilling and underbalanced drilling in deep shale oil and gas reservoirs.

国家自然科学基金项目“气体非平衡溶解对深井气侵井筒气–液两相流影响机制研究”（编号：52104009）、中国石化科技攻关项目“涪陵页岩气田提高采收率技术研究”（编号：P22183）和“页岩气超长水平段水平井钻完井关键技术研究”（编号：P22095）、中国石化页岩油气钻完井及压裂重点实验室开放基金项目“页岩油气长水平井钻井管柱与岩屑床耦合摩阻机理及优化研究”（编号：35800000-23-ZC0613-0005）联合资助

https://doi.org/10.11911/syztjs.2023089