建立了考虑气体吸附、解吸引起的煤基质孔隙变形与孔隙气体压力耦合作用的煤层气藏渗流数学模型,并基于阜新刘家煤层气藏建立了复杂地质条件下褶曲状的煤层气藏地质模型,对比分析了煤层气排采过程中普通储层和复杂地质条件储层的压力变化.模拟得到:煤层气井排采引起的压力分布为沿面割理渗透率方向扩展的椭圆形漏斗,复杂地质条件煤层气藏储层压力主要沿岩墙和断层等封闭条件的走向方向降落;LJ-1～LJ-4四口井处于断层和火成岩三面封闭的条件中,在排采135 d后产生共同的压力降落圈,LJ-5～LJ-8由于处在两道岩墙和两条断层地面四面封闭的环境中,排采45 d形成共同的压力降落圈.同样条件下,无封闭边界构造的普通储层在排采75 d后,7口井周形成共同的压力降落圈.根据煤层气井距岩墙和断层远近的不同,普通煤层气藏气井产量与复杂地质条件煤层气藏气井产量出现3种不同的变化形态.%CBM reservoir mathematical model considering the coupling of matrix pore deformation and pore pressure during gas adsorption and desorb was established, and CBM reservoir geologic model with saddle fold under complicated geological conditions based on Liujia CBM reservoir was established,and pressure change of complicated CBM reservoir exploitation was contrasted to ordinary reservoir. From simulation results, pressure distribution owing to CBM wells exploitation is oval funnel spreading along permeability of face cleat, pressure of complicatedly geologic CBM reservoir spread along the direction of intrusive dykes and faults;the number of LJ-1 to LJ-4 wells are in the region which has three boundaries with the faults and igneous rocks, after 135 day exploitation, four wells are in the same pressure ring;the number of LJ-5 to LJ-8 wells are in the region which has four boundaries with the faults and igneous rocks, after 45 day exploitation, three wells are in the same pressure ring. Under the same conditions, after 75 day exploitation, all wells are in the same pressure ring in ordinary reservoir. There are three different patterns of CBM wells productivity in complicated geological reservoir comparing with ordinary reservoir based on the different distance from well to intrusive dykes and faults.
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