考虑吸附膨胀应力影响的煤层瓦斯流–固耦合渗流数学模型及数值模拟  

MATHEMATICAL MODEL AND NUMERICAL SIMULATION OF FLUID-SOLID COUPLED FLOW OF COAL-BED GAS CONSIDERING SWELLING STRESS OF ADSORPTION

作　　者：李祥春[1] 郭勇义[2] 吴世跃[3] 聂百胜[1] 

机构地区：[1]中国矿业大学资源与安全工程学院,北京100083 [2]太原科技大学,山西太原030024 [3]太原理工大学,山西太原030024

出　　处：《岩石力学与工程学报》2007年第A01期2743-2748,共6页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家重点基础研究发展规划(973)项目(2005CB221502);国家"十五"科技攻关项目(2005BA813B–3–09);国家自然科学基金资助项目(50404015)

摘　　要：已有研究表明,煤吸附瓦斯后要发生相应的膨胀变形,而当这种膨胀变形受到一定的限制时,将会产生膨胀应力。为此,在考虑煤吸附瓦斯产生膨胀应力的前提下,根据煤体受力平衡条件建立考虑吸附膨胀应力的煤体有效应力表达式,并根据流–固耦合渗流理论的基本思想,建立煤层瓦斯流–固耦合数学物理模型。采用有限元和有限差分相结合的方法对模型进行离散化处理,并对其进行模拟求解。和未考虑吸附膨胀应力的流–固耦合模型的模拟结果进行比较分析,研究成果表明,未考虑吸附膨胀应力的流–固耦合模型计算的压力下降较该模型要小,两种模型的模拟结果存在一定的差别,从而表明在煤层瓦斯流–固耦合数学模型中应考虑吸附膨胀应力的影响。Lots of researches have proved that adsorbed gas-coal can generate swelling deformation and when the swelling deformation is restricted,swelling stress can be produced.Thus,according to the equilibrium condition of load,the relations of effective stress and swelling stress of coal are studied;and the expressions of effective stress and swelling stress are established.Based on the expressions and the basic idea of fluid-solid coupling seepage theory,the mathematical model of fluid-solid coupled flow of coal-bed gas,which considers the swelling stress of adsorption,is proposed;and the finite difference method and finite element method are employed to calculate the numerical value.By comparing the simulation results of fluid-solid coupled flow without considering the swelling stress of adsorption,it is shown that gas pressure with decreases more much than that without considering the swelling stress of adsorption.So the swelling stress of adsorption can not be ignored.

关 键 词：采矿工程 有效应力 吸附膨胀应力 瓦斯渗流 流-固耦合 

分 类 号：TD32[矿业工程—矿井建设]