垂直井筒内超临界蒸汽流动过程中的传热特性计算与分析  

Calculation and analysis of heat transfer characteristics during supercritical steam flow in vertical wellbore

作　　者：庞占喜[1,2] 高辉 张泽权 王陆亭 PANG Zhanxi;GAO Hui;ZHANG Zequan;WANG Luting(State Key Laboratory of Petroleum Resources and Prospecting,Beijing City,102249,China;College of Petroleum Engineering,China University of Petroleum(Beijing),Beijing City,102249,China;Sinochem Energy Logistics Co.,Ltd.,Sinochem Group Co.,Ltd.,Beijing City,100031,China)

机构地区：[1]油气资源与探测国家重点实验室,北京102249 [2]中国石油大学(北京)石油工程学院,北京102249 [3]中国中化集团有限公司中化能源物流有限公司,北京100031

出　　处：《油气地质与采收率》2021年第3期111-118,共8页Petroleum Geology and Recovery Efficiency

基　　金：国家自然科学基金项目“多孔介质中纳米颗粒与发泡剂协同构建Pickering泡沫机制及其运移规律”(52074321);北京市自然科学基金项目“缝-孔-喉多尺度介质中泡沫群的裂缝壁面滑移机制与传播过程”(3192026)。

摘　　要：为了系统研究超临界蒸汽在井筒中的流动规律并准确计算其流动过程中的传热特性与热损失量,在对超临界蒸汽的物理化学性质进行数学描述的基础上,综合考虑超临界蒸汽的物理化学性质及其流动过程中的传热规律,基于质量守恒、动量守恒与能量守恒原理,建立了垂直井筒内超临界蒸汽流动过程中的热损失计算数学模型并进行了相应的敏感性分析。研究结果表明,井筒内超临界蒸汽的压力随井深增加而增大,温度随井深增加而降低;对于3000 m井深而言,当注汽速率达到12 t/h时,井筒沿程温度呈现略微降低后又逐渐升高的波动特征,而当注汽速率为8 t/h时,温度降低后在井深约为850 m处开始增加,至约2300 m处又逐渐降低;初始注汽温度越高,井筒沿程温度下降越快,同时压力升高越快,在井深为1000 m处,注汽温度为400℃时的温度降低幅度仅为0.45%,而注汽温度为450℃时的温度降低幅度却达到5.17%;超临界蒸汽流动过程中,如果注汽速率过低或井筒深度过大,均会呈现相态转变特征,注汽速率为2 t/h时的相态转变深度约为1000 m,而注汽速率为4 t/h时的相态转变深度约为2150 m。To systematically research the flow law of supercritical steam in the wellbore and accurately calculate the heat transfer characteristics and thermal loss during the flow,we construct mathematical model to calculate the heat loss during supercritical steam flow in the vertical wellbore based on the principles of mass conservation,momentum conservation and energy conservation.The model comprehensively considers the physicochemical properties of supercritical steam and its heat transfer law during flow.Finally,a series of calculations are completed for the sensitivity analysis of parameters.The results demonstrate that the pressure of supercritical steam in the wellbore grows while the temperature decreases with a rise in well depth.When the steam injection rate reaches 12 t/h,the temperature along the wellbore reduces slightly and then rises at a well depth of 3000 m.However,when the steam injection rate is 8 t/h,the temperature,after decreasing first,begins to increase at a well depth of about 850 m and then declines at about 2300 m.At higher initial temperature of steam injection,the temperature drops faster while the pressure rises more swiftly along the wellbore.At a well depth of 1000 m,the temperature drop is only 0.45%at the steam injection temperature of 400℃,while it is 5.17%at 450℃.In addition,during supercritical steam flow,phase transition will be observed at the over low steam injection rate or the overlarge wellbore depth. The depth of phase transition is about 1 000 m at the steam injection rate of 2 t/h,while it is about2 150 m at 4 t/h.

关 键 词：超临界蒸汽 垂直井筒 数学模型 传热特性 稠油 

分 类 号：TE345[石油与天然气工程—油气田开发工程]