裂缝性低渗透储层压裂液滤失计算新模型

NEW MODEL OF THE FILTRATELOSS OF FRACTURING FLUID IN NATURALLY-FRACTURED AND LOW-PERMEABILITY FORMATIONS

李勇明 赵金洲 郭建春 崔慧芝 王万迅

Li Yongming Zhao Jinzhou Guo Jianchun Cui Huizhi W ang W anxun

西南石油学院油气藏地质及开发工程国家重点实验室, 四川成都 610500 华北油田公司, 河北任丘 062552

现有的压裂液滤失计算方法基本上是基于滤失速度与滤失时间的平方根成反比的经典滤失理论,不能用于裂缝性储层压裂液的滤失计算。在考虑压裂过程中压裂液分别沿天然裂缝和基质向地层渗滤的基础上,建立了裂缝性低渗透储层压裂液滤失计算新模型,采用正交变换法给出了模型的精确解。该模型易于收敛,计算速度快。计算结果表明,裂缝性储层实施压裂作业时,压裂液主要经由天然裂缝滤失,裂缝性储层压裂液滤失计算不能采用经典的滤失理论。

The existing models for filtration rate modeling are based on the classic filtrateloss theory that filtrateloss velocity is inverse proportional to the exponent 1/2 of filtrateloss time, so they can’t be used to filtration rate modeling in naturally fractured formations. To take account of fracturing fluid leaking into the formation through natural fractures and the matrixes, a new model is set up in this paper for modeling fluid filtration rate in naturally-fractured and low-permeability formations and its exact solution is present by means of orthogonal transformation,the new model is easier to convergence and has a fast counting velocity.It is shown from study that the fluid filtration rate in naturally-fractured formations should not use the classic filtration rate theory

10.3969/j.issn.1000-7393.2004.05.014