非常规气藏压裂水平井缝网—井网自动优化方法

非常规气藏已经成为中国油气增储上产的主要阵地，压裂水平井缝网—井网自动优化技术是实现非常规气藏高效开发的关键技术。基于油气藏数值模拟方法，采用同步扰动随机逼近算法建立了压裂水平井单井自动优化模型，对水平井位置、水平井长度、水平井倾角、裂缝与水平井夹角、裂缝条数和裂缝导流能力等关键参数进行自动连续性同步优化，并在典型非均质气藏中对压裂水平井单井参数进行了优化应用。采用该优化方法可以自动优化初始开发方案，得到经济净现值最佳的开发方案。在此基础上，对压裂水平井和裂缝的位置进行约束，建立了压裂水平井缝网—井网自动优化模型。并将该方法应用于典型非均质气藏，优化后的最佳开发方案经济净现值比初始开发方案增加了2 699.688万元。研究表明该压裂水平井缝网—井网自动优化方法能够自动同步优化井网形式、布井数目、水平井倾角和长度、射孔位置及裂缝属性等参数，并得到与地质情况相匹配的最优压裂水平井井网分布。

Automatic optimization method of fracture pattern and well pattern for fractured horizontal wells in unconventional gas reservoirs

Unconventional gas reservoirs have become the main position of increasing oil and gas storage and production in China. Automatic optimization method of fracture pattern and well pattern for fractured horizontal wells is the key technology to achieve efficient development of unconventional gas reservoirs. In this paper, based on the numerical simulation method of oil and gas reservoirs, a single-well automatic optimization model for fractured horizontal wells is established by using simultaneous perturbation stochastic approximation. The key parameters of horizontal well position, horizontal well length, horizontal well inclination, the angle between fracture and horizontal well, the number of fractures and the fracture conductivity are automatically and continuously optimized. The single-well parameters of a fractured horizontal well are optimized in a typical heterogeneous gas reservoir. The research shows that the method can automatically optimize the initial development scheme, and get the development scheme with the best economic net present value. Based on this, the positions of the fractured horizontal wells and fractures are constrained, an automatic optimization model of fracture pattern and well pattern for fractured horizontal wells is established. The fracture parameters and well pattern parameters are simultaneously optimized in a typical heterogeneous gas reservoir, the economic net present value of the optimal development scheme increased by RMB 26.996 88 million compared with the initial development scheme. The research shows that the automatic optimization method of fracture pattern and well pattern for fractured horizontal wells proposed in this paper can automatically and synchronously optimize parameters such as well pattern, number of wells, horizontal well inclination and length, perforation position, and fracture properties to obtain the optimal fractured horizontal well pattern distribution that matches the geological conditions.