基于裂隙分形维数的煤储层压力动态分析  

Pressure Transient Analysis of Coal Seams Based on the Fractal Dimension of Fractures

作　　者：张先敏[1] 同登科[1] 胡爱梅[2] 

机构地区：[1]中国石油大学,山东东营257061 [2]中联煤层气有限责任公司,北京100011

出　　处：《天然气地球科学》2008年第3期433-436,共4页Natural Gas Geoscience

基　　金：国家高技术研究发展计划项目(编号:2006AA06Z236);国家重点基础研究发展计划项目(编号:2002CB211708)联合资助

摘　　要：传统的煤层气渗流数学模型均是建立在欧几里德几何基础上的。以分形理论为基础,引入了分形维参数来刻画煤储层裂隙分形特性,在考虑了煤层的吸附特性、双重介质特征及介质变形的情况下,建立了只考虑裂缝发生形变的分形煤层气藏非平衡吸附、拟稳态条件下气体单相流动数学模型,并采用Newton法求得了该模型的数值解,讨论了无因次压力对模型参数的敏感性,绘制了典型压力曲线。认为此模型可为煤层气开采提供理论依据和新的试井模型。Conventional flow mathematical models of coalbed methane are all based on Euclidean geometry. In this paper, new mathematical models based on the fractal theory are established by introducing fractal parameters to describe the fractal characteristics of the fractures in coal seams. The new models consider not only the double porosity and absorption of coal seams but also the deformation of medium. The numerical solutions are obtained by using the Newton method. The change rules of pressure are discussed when the parameters of models change. The plots of typical pressure curves are given, and the results provide theoretical basis and new well test methods for the exploitation of coalbed methane.

关 键 词：煤层气 分形维数 非平衡吸附 NEWTON法 

分 类 号：TE132.2[石油与天然气工程—油气勘探]