在CO₂驱替增强开采过程中，煤层裂隙行为对封存/采收有显著影响。为了解决多物理场耦合效应下裂隙粗糙度演化对工程效率影响尚不明确的难题，建立了一种创新的跨学科数学模型，提出定量描述煤层裂隙粗糙度的参数，并将其与煤层多场效应下的气体流动控制方程耦合，研究了煤层瓦斯开采过程中的热-流-固耦合效应及裂隙网络特性。结果表明：数学模型与实地数据吻合良好，能够表征煤层裂隙粗糙度；裂隙粗糙度对煤层瓦斯剩余压力及注入CO₂气压有显著影响；当粗糙度参数由0.24降至0.18时，煤层瓦斯含量最大降低32.5%，CO₂压力最大增加26.7%，煤层瓦斯吸附量最大降低31.7%，CO₂吸附量最大升高12.1%。

In the process of CO₂-enhanced coalbed methane recovery, the behaviours of coal seam fractures significantly affect sequestration and extraction. To address the unclear impact of fracture roughness evolution on engineering efficiency under multi-physical field coupling effects, we developed an innovative interdisciplinary mathematical model. This model introduces a parameter to quantitatively describe coal seam fracture roughness and couples it with the gas flow control equations under multi-field effects in the coal seam. We investigated the thermo-hydro-mechanical (THM) coupling effects and fracture network characteristics in the coal seam gas extraction process. Results show that the mathematical model aligns well with field data and effectively characterizes coal seam fracture roughness. Fracture roughness significantly influences the residual gas pressure in the coal seam and the injection pressure of CO₂. When the roughness parameter decreases from 0.24 to 0.18, the maximum methane content decreases by 32.5% and the maximum CO₂ pressure increases by 26.7%, the maximum gas adsorption capacity of coal seam decreased by 31.7%, and the maximum CO₂ adsorption capacity increased by 12.1%.