压裂防砂过程中裂缝内净压力模拟计算

Calculation of net pressure in fractures during FracPac process

压裂防砂施工过程中缝内净压力变化复杂,这是施工成功的关键问题。针对压裂防砂技术的实际特点,将受压力控制的PDFL滤失模型和经典的KGD裂缝延伸模型结合起来,对施工过程中裂缝尺寸及缝内净压力变化进行了模拟计算,并得到了现场井例数据的验证。把压裂防砂整个施工过程分成脱砂前、后2个阶段,对这2个阶段分别编制了计算框图,并根据计算框图编制程序对缝内净压力的变化进行模拟计算,得到了完整的净压力曲线。

Reservoir permeability and pressure changes are complicated in the construction process, which is the key to the success of the construction process. The paper builds up a PDFL leakoff model and a KGD fracture extended model to compute the changes of fracture geometry and pressure in the fracture. The theory and application program in this paper has been verified by the oil well data of Shengli Oilfield. The process of Frac and pack is divided into two stages of pre- and post desanding, computing programs are compiled respectively for the two stages, based on which modeling calculation is carried out for net pressure changes in the fractures and complete net pressure curve has been obtained.