大规模压裂改变了煤层气低产、低效的开发现状，但煤层气压裂井生产动态不清晰、渗透率演化机制不明确，极大地限制了煤层气藏的高效开发。为此，考虑煤层吸附膨胀、裂缝压缩和非稳态蠕变条件下的总应变演化，结合立方定律建立渗透率模型，利用有限体积法(FVM)结合瞬态嵌入式离散裂缝模型(tEDFM)求解压力和渗透率场。依托嵌入式流量交换原理，建立吸附−游离多重采出计算框架，实现压后生产动态分析和产能计算。研究发现：煤层气压裂井生产动态包括初期高产、解吸上升、中期稳产、后期衰减和末期枯竭5个阶段。兰氏压力越大，吸附气上产越快，兰氏压力为2.6 MPa时，1 800 d后吸附气主导生产。兰氏体积增加至15 m³/t，解吸附贡献占比持续上升，吸附态甲烷在560 d后成为主要气源。水力裂缝越密集，泄压面积增大显著提升初期产能且衰减越晚。裂缝间距增大3倍，最高产气量减少48 %，裂缝半长增加50 m，初期产量增加近一倍。渗透率演化包括损失、恢复和增强3个阶段，裂缝压缩系数为0.03 MPa⁻¹，800 d内损失率高达76 %。尽管裂缝闭合造成渗透率损失，当甲烷解吸并采出，膨胀应变减小，使得渗透率进入恢复阶段。压裂规模增大，渗透率恢复越快且程度更高，促进煤层气长效采出。当解吸附应变大于0.06，渗透率在生产后期可恢复并增强至初期的1.2倍。煤层黏弹性模量越低，蠕变造成的渗透率损伤越明显。

Massive hydraulic fracturing has changed the status of low-productivity and low development efficiency for coalbed methane (CBM) reservoirs. However, the production dynamics of fractured wells and the permeability evolution mechanisms in CBM reservoirs are unclear, which significantly limits the efficient development of CBM reservoirs. Therefore, this study incorporates the total strain evolution under the conditions of gas-adsorption-induced swelling, fracture compression, and unsteady creep, uses the cubic law to establish the permeability model, and obtains the pressure and flow fields via the finite volume method (FVM) and the transient embedded discrete fracture model (tEDFM). Based on the embedded mass exchange law, an adsorbed-free phase multiple-mechanism recovery calculation framework is established to realize production dynamic analysis and productivity calculation. Results show that the production dynamics of CBM fractured wells include five stages: the initial high production stage, desorption-induced productivity increasing stage, mid-time stable production stage, production decline stage, and the final depleted stage. The larger the Langmuir pressure is, the faster sorbed gas production would be. When the Langmuir pressure is 2.6 MPa, after 1 800-day production, adsorbed gas dominates production. When the Langmuir volume is increased to 15 m³/t, desorbed gas’s contribution continuously increases. Adsorbed gas becomes the main gas source after 560-day production. The denser the hydraulic fractures are, the larger the drainage area is, the significantly higher the initial production would be, and the later the production decline occurs. When the fracture spacing is 3 times larger, the maximum gas production decreases by about 48%. When the fracture half-length is increased by 50 m, the initial production would nearly be doubled. The permeability evolution includes three stages: loss, recovery, and enhancement. When the fracture compressibility coefficient is 0.03 MPa⁻¹, and the loss rate is as high as 76% within 800 days. Despite the loss of permeability due to fracture closure, when the methane is desorbed and recovered, the reduction of swelling strain causes the permeability to recover. With fracturing intensity increases, and the permeability recovery becomes faster and stronger, which promotes the long-term recovery of CBM. When the desorption-induced strain is greater than 0.06, the permeability recovers and increases to 1.2 times the initial level in the later production period. The lower the coal viscoelastic modulus is, the more obvious the permeability damage caused by creep would be.