摘要
基于点源函数理论和边界元思想,建立一种可用于致密油藏直井体积压裂改造非稳态压力分析的半解析模型。模型考虑改造区与未改造区储层非均质性的影响,在均质条件下与解析解进行对比与拟合,并应用已建立的模型对改造区与未改造区渗透率差异性、体积压裂改造程度、改造面积和形态、主裂缝长度及导流能力等参数进行讨论。结果表明:随着改造区内渗透率的增大,压力损耗减小,受改造区面积的影响,单一提高改造区的地层渗透率对整体压力影响较小;相同的储层改造体积情况下,有效裂缝体积较大的开发效果最好。与常规压裂相比,体积压裂井的开发效果主要受主裂缝长度的影响而非导流能力。
On the basis of source function,a semi-analytical model for transient pressure behaviors of volume fractured vertical wells in rectangular tight oil reservoirs is obtained.The effect of heterogeneity between reconstruction region and unmodified region is considered.The model and corresponding solution are validated by comparison the transient pressure responses calculated with previous solution.The effects of various parameters such as the difference of permeability between the inner and outer region,storability ratio,inter-porosity flow coefficient ratio,area and shape of reconstruction region,half length and conductivity of primary hydraulic fracture are also analyzed.The results show that with the increase of permeability in the reconstruction region,the pressure loss under the same rate decreases.However,only improving the permeability of reconstruction region has little effect on the overall pressure.When the area of reconstruction region is constant,the development effect of larger effective reconstruction region is better.Compared with conventional fracturing,the development effect of volume fracturing is influenced by the length of primary hydraulic fracture rather than the conductivity.
出处
《东北石油大学学报》
CAS
北大核心
2017年第2期103-113,共11页
Journal of Northeast Petroleum University
基金
国家自然科学基金项目(51674227)
关键词
点源函数
半解析
矩形致密油藏
储层改造
渗透率差异性
导流能力
裂缝半长
point source function
semi-analytical
rectangular tight oil reservoirs
reservoir reconstruction
permeability difference
fracture-conductivity
fracture half length
