Fault block Tai 27 in Wuliyasitai Oilfield is a typical low-permeability oil reservoir, and it has a certain production capac-ity after fracturing stimulation. To optimize the overall fracturing parameters of fault block Tai 27, history matching of production wells was carried out by means of numerical simulation to verify the reliability of non-Darcy flow model with starting pressure gradient and mathematical model of overall fracturing. Then, the overall fracturing design of inverted nine-spot well pattern in fault block Tai 27 in Wuliyasitai Oilfield was optimized. The effects of fracture length ratio and conductivity on oil well productivity were analyzed. Devel-opment schemes for different combinations of fracture parameters were designed and optimized by using the orthogonal design method. The simulation results show that the fracture parameters suitable for fault block Tai 27 are as follows. The fracture semi-length in well injectors is 44 m. The conductivity is 10 D·cm in well injectors and 20 D·cm in corner wells. The ratio of fracture length to distance be-tween wells is 0.3 (semi-length of fractures 66 m) in edge wells and 0.45 (fracture semi-length 99 m) in corner wells. It is indicated that in a given well pattern, there is an optimal fracture length and an optimal conductivity, but the highest may not be the best. The researchresults can be used as the reference for the overall fracturing of other low-permeability oil reservoirs.%乌里雅斯太油田太27断块属于典型的低渗透油藏,经过压裂改造后才具有一定的生产能力.为了优化太27断块的整体压裂参数,在考虑启动压力梯度的非达西渗流模型和整体压裂数学模型的基础上,采用数值模拟对生产井进行了历史拟合以验证模型的可靠性,并对乌里雅斯太油田太27断块反九点井网进行了整体压裂优化设计,分析了不同裂缝缝长比和导流能力对油井产能的影响.同时采用正交设计方法,设计了不同裂缝参数组合下的开发方案并进行优化.模拟结果表明,适合太27断块的裂缝参数为水井半缝长44 m,水井导流能力10 D·cm,边井缝长比0.3(半缝长66 m),角井缝长比0.45(半缝长99 m),角井导流能力为20 D·cm.在给定的井网条件下,裂缝缝长和导流能力存在最优值且并非越大越好,为其他低渗油藏区块整体压裂方案的设计提供技术参考.
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