煤矿安全2025，Vol.56Issue(4)：43-49,7.DOI:10.13347/j.cnki.mkaq.20231815
含瓦斯煤体水气分布及渗流规律数值模拟
Numerical simulation of water and gas distribution and seepage law in coal containing gas
摘要
Abstract
In order to investigate the influence of water-gas domain distribution on the relative permeability of water and gas during the injection of hot water into coal,we establish a two-dimensional pore cavity throat model based on fractal theory,and use the wa-ter gas dynamic equilibrium equation as the judgment condition for seepage calculation.The water and gas balance control equation of the cavity throat network was derived,and the distribution law of the water-gas domain during coal seam thermal injection and drainage gas production process was clarified.Finally,the relationship between water injection pressure,fractal dimension,temperat-ure and relative permeability was obtained.In the study of constant temperature water injection process,it was found that as the in-jection pressure increases,the gas chamber is constantly occupied by water,the saturation of water continuously increases,and the relative permeability of water significantly increases.The injection pressure is positively correlated with the relative permeability of water.During the constant pressure heating and drainage process,the increase of free methane leads to an increase in gas pore pres-sure in the model,overcoming capillary forces to discharge water.The temperature is higher,the water chamber is occupied by the gas chamber,and the distribution of the gas domain is wider.When percolation occurs,the relative permeability of the gas increases sharply,which is positively correlated with temperature and conducive to the discharge of water.关键词
煤层气/瓦斯抽采/孔腔-孔喉结构/逾渗/相对渗透率/水-气域分布/分形维数Key words
coalbed methane/gas drainage/pore cavity throat structure/percolation/relative permeability/water gas domain distri-bution/fractal dimension分类
矿业与冶金引用本文复制引用
蔡靖哲,周动,王刚,姬宇辉,郑欣欣..含瓦斯煤体水气分布及渗流规律数值模拟[J].煤矿安全,2025,56(4):43-49,7.基金项目
国家自然科学基金资助项目(12102293) （12102293）
