During fracturing of horizontal tight oil wells, describing fracturing network and optimizing fracture parameters are the key to improve well capacity. For the problem that fracture parameters of horizontal wells are difficult to determine, in this paper, according to hydro similarity theory, electric analogy experiments were designed to study how pressure distri-bution near staged cluster fractured horizontal wells and fracture parameters ( including the distance among clusters, length of fractures, and the number of natural fractures, etc. ) affect single-well productivity. Results showed that staged cluster fracturing improved reservoir liquidity near the well, and the network sourcing from artificial and natural fractures was favor-able for improving crude oil flow capacity. When fracture length and staged distance are determined, single well output may rise with increased natural gas fractures. Well yield could be more increased by vertical fracturing than oblique fracturing. Fractures at both ends contribute the most to oil output which declines to the middle, and the fractures in the middle con-tribute the least to output. The study provides a theoretical support for reasonable and effective tight oil development.%在致密油水平井压裂中, 描述裂缝网络、 优化裂缝参数是提高产能的关键所在, 针对水平井压裂裂缝参数难以确定的问题, 利用水电模拟方法对分段多簇压裂水平井近井压力分布及裂缝参数 (包括簇间距、 裂缝长度、 天然裂缝数量等) 对单井产能的影响进行了电模拟实验研究. 实验结果表明, 分段多簇压裂改善了近井地带储层的流通性, 人工裂缝与天然裂缝形成缝网有利于改善原油流动能力. 在压裂裂缝长度和段间级距一定时, 随着天然裂缝数量的增加, 单井产量增加; 垂直裂缝比斜交裂缝更能提高单井产量; 水平井两端的裂缝产量贡献最大, 向中间依次递减, 最中间的裂缝产量贡献最小. 本研究为合理、 有效开发致密油提供理论支持.
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