Breakdown of doublet recirculation and direct line drives by far-field flow in reservoirs: implications for geothermal and hydrocarbon well placement
Breakdown of doublet recirculation and direct line drives by far-field flow in reservoirs: implications for geothermal and hydrocarbon well placement
复制标题
DOI：
10.1093/gji/ggw135
复制
发表时间：
2016-07
影响因子：
2.8
通讯作者：
R. Weijermars;A. V. Harmelen
中科院分区：
文献类型：
--
作者：
R. Weijermars;A. V. Harmelen
双重流的一个重要的真实的世界应用出现在地热和碳氢化合物储层的井设计中。注入井和开采威尔斯井的流体管理的指导原则是通常假设注入流体和产出流体之间的质量平衡。因为双合井被认为是闭合回路，所以假设注入流体最终到达生产井，并且所有生产的流体理想地来自连接到构成双合井的井对的注入器的流管。我们发现，当含水层背景流发生，双峰将很少保留封闭的循环流体再循环。当远场流率相对于偶极子的强度增加时，偶极子所占据的面积将减小并最终消失。或者，不是使用单个注入器（源）和单个生产器（汇），而是可以在地热能项目中以及在碳氢化合物储层的注水中使用与生产器的平行阵列隔开一定距离的多个注入器的线性阵列。流体流动在这样一个平行的源-汇阵列的安排被证明是宏观上相当于一个线偶极子。同样，任何足够强的远场流将突破线偶极子，然后分裂成两个漩涡。除了对基本流动动力学的基本见解外，我们的新结果还提供了实用的线索，可能有助于改善通常用于地下水，地热和油气藏流动管理的双合管和直线驱动器的规划和设计。
S U M M A R Y An important real world application of doublet flow occurs in well design of both geothermal and hydrocarbon reservoirs. A guiding principle for fluid management of injection and extraction wells is that mass balance is commonly assumed between the injected and produced fluid. Because the doublets are considered closed loops, the injection fluid is assumed to eventually reach the producer well and all the produced fluid ideally comes from stream tubes connected to the injector of the well pair making up the doublet. We show that when an aquifer background flow occurs, doublets will rarely retain closed loops of fluid recirculation. When the far-field flow rate increases relative to the doublet’s strength, the area occupied by the doublet will diminish and eventually vanishes. Alternatively, rather than using a single injector (source) and single producer (sink), a linear array of multiple injectors separated by some distance from a parallel array of producers can be used in geothermal energy projects as well as in waterflooding of hydrocarbon reservoirs. Fluid flow in such an arrangement of parallel source-sink arrays is shown to be macroscopically equivalent to that of a line doublet. Again, any far-field flow that is strong enough will breach through the line doublet, which then splits into two vortices. Apart from fundamental insight into elementary flow dynamics, our new results provide practical clues that may contribute to improve the planning and design of doublets and direct line drives commonly used for flow management of groundwater, geothermal and hydrocarbon reservoirs.