考虑水力裂缝导流能力衰减的直井注水能力预测模型  

Prediction Model of Water Injection Capacity of Vertical Well Considering the Attenuation of Hydraulic Fracture Seepage Ability

作　　者：赵传峰[1] 曹博文 王冰飞 臧雨溪 王大未 ZHAO Chuanfeng;CAO Bowen;WANG Bingfei;ZANG Yuxi;WANG Dawei(Research Institute of Unconventional Resources,China University of Petroleum (Beijing),Beijing 102249,China;Beijing Branch,China Petroleum Engineering & Construction Corporation,Beijing 100120,China)

机构地区：[1]中国石油大学(北京)非常规油气科学技术研究院,北京102249 [2]中国石油工程建设公司北京分公司,北京100120

出　　处：《西安石油大学学报（自然科学版）》2020年第4期47-52,共6页Journal of Xi’an Shiyou University（Natural Science Edition）

基　　金：中国石油天然气股份有限公司重大科技专项“昆北油田裂缝表征及低效井重复压裂可行性研究”(2016E-0105)。

摘　　要：基于等值渗流阻力原理建立了一个压裂直井注水能力预测的解析模型。根据导流能力或渗透率的非均质性首先对裂缝分段及对基质分区。模型中各裂缝段和基质区的属性可以在缝长方向上随时间变化呈现衰减。在同一条裂缝段及对应的基质区内的流动为双线性流。注入的流体从注水井流入裂缝,并依次流经各裂缝段进入对应的基质区。给定初始条件和裂缝导流能力在缝长方向上随时间的衰减规律等,便可根据该模型确定直井的注水能力以及各裂缝段的流量和压力。对比发现,该模型的计算结果具有较高的预测精度,接近于数值模拟解,优于已有模型的解析解。算例表明,注水裂缝内的流体流量和压力沿着缝长方向逐渐降低,降低幅度呈现先急后缓的特点;相对于裂缝导流能力的空间衰减,其时间衰减对缝内流量和压力分布的影响更加明显。An analytical model for predicting the water injection capacity of vertical fracturing water injection well is established based on the principle of equivalent seepage resistance.The fracturing fracture is segmented and the matrix is partitioned according to the heterogeneity of seepage capacity or permeability.In the model,the properties of fracture segments and matrix zones decrease with time in the direction of fracture length.In the same fracture section and the corresponding matrix area,the fluid flow is bilinear flow.The injected fluid flows into the fracture from the water injection well,and then flows through each fracture section to the corresponding matrix area.Given the initial conditions and the attenuation law of fracture seepage capacity along the fracture propagation direction,the water injection capacity of vertical well and the flow rate and pressure of each fracture section can be determined according to the model.It is found that the model have high prediction accuracy,its calculation results are close to the numerical simulation solution and better than the analytical solution of the existing prediction models.The example shows that the fluid flow-rate and pressure in the fracturing fracture gradually decrease along the fracture propagation direction,and the decrease rate is rapid first and then slow down;Compared with the spatial attenuation of fracture seepage capacity,its time attenuation has more obvious influence on the flow-rate and pressure distribution in the fracture.

关 键 词：注水能力预测模型 水力裂缝 导流能力 压裂直井 

分 类 号：TE312[石油与天然气工程—油气田开发工程]