重复压裂裂缝转向的ANSYS有限元模拟  

Finite-element Simulation Analysis of Re-fracture Reorientation Based on ANSYS

作　　者：张公社[1] 赵蓓[1] 石惠宁[2] 宋时权[3] 

机构地区：[1]长江大学石油工程学院,湖北荆州434023 [2]华北油田分公司采油工艺研究院,河北任丘062550 [3]胜利油田有限公司采油工艺研究院,山东东营257000

出　　处：《石油天然气学报》2009年第6期141-144,共4页Journal of Oil and Gas Technology

基　　金：中国石油天然气总公司重大专项研究项目(CNPC2007-20071209)

摘　　要：运用ANSYS10.0软件对重复压裂的应力场进行了模拟计算,结果表明初次人工裂缝的存在,引起近井眼处应力极大值与极小值发生转向,重复压裂将产生垂直于初次裂缝方向上的新裂缝。根据断裂力学应力强度因子准则对重复压裂新裂缝的转向过程进行了有限元模拟,绘出了新裂缝转向的轨迹;重复压裂新裂缝开始垂直于初次人工裂缝,在延伸过程中进行不断地转向,最终基本和水平最大主应力方向平行。Refracturing was a main method to stimulate and beneficiate low permeability oilfields.The re-fracturing stress field was simulated by ANSYS 10.0.The calculation results indicate that the existence of initial artificial cracks can reorientate the maximum and minimum stress near wellbore,thus a new crack perpendicular to the initial cracks is produced.According to the fracture mechanics of stress intensity factor,finite element simulation is used to draw the steering process of the new crack.The new re-fracturing cracks perpendicular to the initial cracks is steered continuously in the extending process,and finally is parallel to the direction of maximum principal stress.

关 键 词：水力压裂 地应力 重复压裂 有限元 ANSYS 

分 类 号：TE357.1[石油与天然气工程—油气田开发工程]