水力裂缝的缝高控制参数影响数值模拟研究  

Numerical simulation of hydraulic fracture height control with different parameters

作　　者：王瀚[1] 刘合[1,2] 张劲[3] 吴恒安[1] 王秀喜[1] 

机构地区：[1]中国科学技术大学近代力学系,安徽合肥230027 [2]中国石油勘探开发研究院,北京100083 [3]中国石油大学(北京)石油和天然气工程学院,北京102200

出　　处：《中国科学技术大学学报》2011年第9期820-825,共6页JUSTC

基　　金：中国石油科技创新基金项目(2010D-5006-0209)资助

摘　　要：水力压裂是低渗油藏增产的重要手段,在工程中有着广泛的应用.以ABAQUS软件为平台,采用平面应变模型模拟油藏的流固耦合力学行为,用基于损伤力学方法的粘性单元模拟裂缝沿高度方向的起裂和扩展过程.对大庆油田某水平井的压裂过程进行数值模拟,得到的井口泵压曲线与现场施工测得的泵压曲线吻合良好,验证了模型的正确性和合理性.采用该模型研究了隔层与产层之间的地应力差、抗拉强度差与弹性模量差之间的耦合作用对裂缝高度的影响.结果表明,隔层的高应力、高强度和低模量能够较好地控制裂缝高度,这些结果对压裂工程设计有很好的参考价值.Hydraulic fracturing is an important way to improve the productivity of the reservoir with low permeability and is widely used in oil engineering.A plane strain model of hydraulic fracture was established with the ABAQUS code.Coupling between solid deformation and fluid flow of the reservoir was considered in the model.The cohesive elements based on damage mechanics were adopted to simulate the initiation and propagation of the fracture height.The hydraulic fracture process of a horizontal well in Daqing was simulated with the present model.And the surface pressure curve obtained by our model was consistent well with what was measured in the field,thus proving the validity of the model.Then,the effects of parameters on the fracture height containment were studied with the proposed model.The parameters include contrasts of the in-situ stress,tensile strength and elastic modulus between the barrier zone and the pay zone.The results indicate that higher in-situ stress,higher tensile strength and lower elastic modulus in the barrier zone could control fracture height well.The conclusions are valuable for engineering design of hydraulic fracture.

关 键 词：水力压裂 有限元 损伤力学 缝高 

分 类 号：TE357[石油与天然气工程—油气田开发工程]