【摘要】 CO₂-ECBM工程具有能源开发和碳减排的双重效益，热–流–力多物理场耦合数值模拟是探究CO₂驱替CH₄的有效方式。本文通过改进表观渗透率模型，对热–流–力全耦合模型进行改进，提出并验证了考虑孔径变化的动态表观渗透率、气–水两相渗流、非等温竞相吸附、煤层应变的热–流–力全耦合模型，并针对主控参数做进一步研究。研究结果表明：表观渗透率受毛细孔和微裂隙尺寸、黏性流动、Kundsen扩散、吸附气表面扩散共同影响。孔裂隙尺寸变化由储层内渗流过程和体积应变决定；储层内流动过程受气体压力和体积应变耦合作用，压力越高黏性流动对表观渗透率的影响越大。对体积应变影响从低到高依次是储层温度、混合气体压力、储层地质条件以及气体吸附/解吸。较高的CO₂注入压力对CH₄产出和CO₂封存具有正向作用。较高的煤层初始温度增加了CO₂气体吸附难度，驱替效果下降，CO₂封存量减少。更多还原

【Abstract】 CO₂-ECBM engineering has the dual benefits of energy development and carbon emission reduction, and the coupled numerical simulation of heat-fluid-force multiphysics is an effective way to explore the replacement of CH₄ by CO₂. In this paper, by improving the apparent permeability model, the thermal-fluid-force fully coupled model is improved, and the dynamic apparent permeability, gas-water two-phase seepage, non-isothermal competitive adsorption, and coal seam strain are proposed and verified, and the main control parameters are further studied. The results show that the apparent permeability is affected by the size of capillary pores and microfractures,viscous flow, Kundsen diffusion, and surface diffusion of adsorbed gas. The change of pore fracture size is determined by the seepage process and volume strain in the reservoir. The flow process in the reservoir is affected by the coupling of gas pressure and volumetric strain, and the higher the pressure, the greater the influence of viscous flow on the apparent permeability. The effects on volumetric strain from low to high are reservoir temperature, gas mixture pressure, reservoir geological conditions, and gas adsorption/desorption. Higher CO₂ injection pressure has a positive effect on CH₄ production and CO₂ sequestration. The higher initial temperature of the coal seam increases the difficulty of CO₂ gas adsorption, the displacement effect decreases, and the CO₂ storage decreases.更多还原