Abstract: Fracture length of fractured well is the important factor to determine the fracturing effect. Taking the diamond shaped inverted nine spot pattern in a block of Xinjiang oilfield as an example, based on the reservoir numerical simulation software.Considering the starting pressure gradient and stress sensitivity, the cumulative degree of reserves recovery of crude oil is simulated under the conditions of different fracture length. The relationship between the reserves recovery degree of hydraulic fracture and comer well, edge well and central well is analyzed. The comparison results show that: the fracture of edge well may give rise to the invasion of injected water, corner well cannot be affected by injection well, causing the precipitous decline of production rate in corner well. For the central injection well, it is not only to reduce the fracture length in order to improve the water drive spread coefficient, but also to ensure that the length of the fracture is enough to supplementary formation energy. The best solution: the diversion capability of fracture is 20 μm2·cm,the fracture length of corner well is 100 to 120 meter, the fracture length of edge well is 50 meter, the fracture length of central well is 50 meter. This conclusion provides new recognition for the optimization of fracture parameters.

Key words: Diamond shaped inverted nine spot pattern,    , Threshold pressure gradient,    , Stress sensitivity,    , Unequal fracture length,    , Numerical simulation

摘要：         压裂井裂缝长度是决定压裂效果的最主要因素之一,以新疆油田艾湖1区块菱形反九点井网为例,考虑边井、角井、中心井在渗流场中的不同位置,应用油藏数值模拟软件,在对油田启动压力梯度和应力敏感性处理基础上,模拟计算不等缝长度组合下压裂井的累积采出程度,详细分析了水力压裂采出程度与角井、边井、中心井的关系。结果表明,边井裂缝会导致边井优先见水,进而导致角井驱替效果变差,产量大幅下降;对于中心注水井,既要降低裂缝长度,提高水驱波及系数,又要有一定的压裂缝长以确保注入水能补充地层能量。模拟得出最佳的裂缝导流能力为20μm²·cm,最佳的角井裂缝半长为100~120m,边井裂缝半长为50m,中心井裂缝半长为50m。

关键词: 菱形反九点,   ,  启动压力梯度,   ,  应力敏感,   ,  不等缝长,   ,  数值模拟