泵流量对纵向切槽水力压裂裂缝偏转的影响规律研究

Influence of Pump Flow to Fracture Gauche of Hydraulic Fracturing with Cutting along Bore Direction

采用ABAQUS软件,建立了纵向切槽水力压裂裂缝扩展的有限元二维模型,分析了不同泵流量条件下纵向切槽水力压裂裂缝扩展规律。研究表明:裂缝开裂初期,受地应力差的影响,裂缝很快转向最大主应力方向;随着泵流量的大幅增加,裂缝的偏转情况得到减缓,曲率半径增大,偏转距明显增加,流量在120L/min以内时,增长速度较快;目前常用注水泵流量为90L/min,其裂缝偏转距为4.05m。结论对于实际的钻孔距设计和注水泵选取具有参考意义。

The finite element tow dimensional model of fracture expanding of hydraulic fracturing with cutting along bore direction was built with ABAQUS software,and then fracture expanding principle under different pump flow were analyzed.The results showed that the fracture direction rapidly turn to the major principal stress orientation at the beginning under influence of crustal stress difference,with pump flow increased largely,and then fracture gauche situation was slowed down,and curvature radius increased,gauche moment increased obviously,it increased rapidly as flow within 120L/min,the gauche moment reached 4.05m under the normal pump flow 90L/min,and the conclusions referenced for drilling distance design and pump selection.