水力压裂垂直裂缝几何形态数值模拟及影响因素分析

NUMERICAL SIMULATIOH AND EFFECT FACTOR ANALYSIS OF VERTICAL FRACTURE GEOMETRY IN HYDRAULIC FRACTURE

建立了均质地层上下地应力为非对称的、适用于一般裂缝几何形态的水力压裂拟三维数学模型，分析了各种因素对裂缝延伸的影响。杨氏模量增大使缝宽下降，而注入流量和压裂液粘度的增加均使缝宽增大，压裂液粘度和杨氏模量增加使缝高增加，地应力差增加使缝高下降。讨论了利用人为因素控制裂缝延伸的方法。用实际施工的一口井资料进行验证，裂缝闭合后的井壁缝高与测井曲线的高度基本一致，其相对误差为５．３％。

A pseudo-three dimensional hydraulic fracture model for a general fracture geometry in the homogenous formation is presented,in which the boundary layer stresses are not equal.Various factors that effect fracture extension are analyzd;fracture width decreases with the increases in Yang's moddel;fracture hight decreases with the increase in stress contrast.The methods to prevent fracture extension are discussed.The test and verification are carried by using the data of a actually fractured well,the fracture hight with shut-in fracture is consistent with the log data,the relative error is5.3%.