体积压裂缝网系统模拟及缝网形态优化研究

Simulation and pattern optimization of volume fracturing fracture network

为了有效地表征压裂后形成的复杂裂缝网络系统,依据三维改造区域的渗流规律,提出了缝网双重介质数值模型。利用该模型对不同缝网形态进行模拟,分析了不同缝网形态对产能的影响规律,并获得衰竭式开发下的最佳形态。研究结果表明:纺锤型与哑铃型缝网形态较其他缝网形态更具优势;影响体积压裂水平井产能的因素主要有端部裂缝的产能、缝网内部裂缝缝间干扰的程度、缝网形态中部主裂缝对泄流面积的控制程度。

In order to effectively characterize complex fracture network,a dual-porosity fracture network numerical simulation model is presented based on the seepage law in studied 3D region. Different fracture patterns are simulated using the model,the effect laws of the fracture patterns on the productivity of horizontal well are analyzed,and the optimal fracture network pattern under depleted development form is obtained. The research results show that: spindle-shaped and dumbbell-shaped networks are superior to other fracture network patterns in depleted development form; the main factors of influencing the productivity of volume fracturing horizontal well are the productivity of the fracture at the end of horizontal borehole,the interference degree extent among the fractures in the network,and the control degree of the main fracture in the middle of fracture network to drainage area. The research results can provide certain guidance for the volume fracturing design of the horizontal well in tight reservoirs.