压裂液滤失的二维数值模拟

结合油藏工程和数值模拟技术 ,根据压裂施工过程中滤失的压裂液在地层中二维流动和压裂液为非牛顿型流体的实际 ,建立了非牛顿型压裂液的二维动态滤失模型 ,用数值方法求解 ,并将计算结果与一维模型结果进行对比分析。计算表明 :仅考虑压裂液垂直于裂缝壁面一维流动所计算的滤失速度会偏小 ,并且这种差值会因地层渗透性的增加而加大。二维方法由于考虑了压裂液的非牛顿特性和二维流动 ,其结果也比一维模型更符合现场实际 ,可以减少压裂施工的风险 ,提高压裂设计的可靠性。

TWO DIMENSIONAL NUMERICAL SIMULATION OF FRACTURING FLUID LEAKOFF

Combining reservoir engineering method and numerical simulation technology, accounting for the non-Newtonian behavior of fracturing fluid and the 2 dimensional flow of filtrate during fracturing operation, a 2D dynamic leakoff model of non-Newtonian fracturing fluid was established. Numerical method was employed to solve this model and the simulation results were compared to that of 1D model. It shows that, the leakoff rate calculated at the consideration of that fracturing fluid leakoff flows in the direction that perpendicular to the fracture face is smaller than that of 2D flow, and their difference increases with formation permeability. The 2D model is more reasonable. Because the non-Newtonian behavior of fracturing fluid and the 2D flow were accounted, this model is more applicable and its simulation results are closer to field. It can reduce the fracturing operation venture and increase the reliability of fracturing design.