三重介质三线性流垂直裂缝井压力动态分析

Analysis on pressure behavior of trilinear flow model of vertical fracture wells
in triple porosity reservoir

蔡明金 吴玉君 贾永禄 谭静 方军

西南石油大学石油工程学院，四川 成都 610500 中国石油化工集团公司石油工程西南有限公司重庆钻井分公司, 重庆 400021 辽河石油勘探局工程技术研究院，辽宁 盘锦124010 吉林油田集团公司井下作业公司，吉林 松原 138001

为了给高效开发低渗透油藏提供依据，针对三重介质油藏进行水力压裂后形成的有限导流垂直裂缝，结合均质油藏三线性流数学模型，应用拉普拉斯变换，求得了三重介质油藏有关裂缝储集和裂缝表皮效应的三线性流模型井底压力表达式。应用Stefest数值反演，绘制了无因次压力及压力导数对时间的双对数特征曲线，对其动态特征及影响因素进行了分析。研究结果表明，其压力动态最显著的影响因素是裂缝储集系数、裂缝表皮系数和无因次导流能力，其它参数对井底压力动态的影响与其对普通直井油藏的影响相类似。

According to the finite-conductivity vertical fractures conducted by hydraulic fracture in triple porosity reservoir, based on the
trilinear flow model in homogeneous reservoir with finite-conductivity vertical fracture, the formulas of downhole pressure in Laplace
space of triple porosity reservoir with fimite-conductivity vertical fracture are obtained through using Laplace transform in order to
provide a basis for the efficient development of low permeability reservoirs. At last, the log-log curves of pressure and its derivative
to time are drawn out and the dynamic characteristics of the bottom hole pressure of finite-conductivity vertical fracture well and its
influence factors have been discussed. It is shown that the fracture storage factor, skin factor and dimensionless conductivity are the
striking effect elements to pressure behavior. However, the influences of other elements on fractured well are similar to ordinary
vertical wells.