Multi-well extraction is a prevalent technique in coalbed methane (CBM) recovery projects. Although numerous studies have extensively explored aspects such as well spacing, the degree of multi-well pumping, and well count, the dynamics of fracture microstructure evolution in proximity to wells—particularly in inter-well regions—remain inadequately understood in relation to the effects of multi-well mining project. This research delved into the multi-well extraction methodology employed in CBM recovery endeavors, aiming to elucidate the development of the fracture microstructure network. We introduce a novel, interdisciplinary, and integrative research framework that amalgamates the multi-field coupling effects observed during the multi-well extraction process with fractal theory. This model has been validated, and it facilitates the examination of changes in fracture micro-evolution subjected to multi-well extraction. Additionally, this study investigated alterations in fracture characteristics, seam stress, and CBM pressure within sensitive zones (i.e., inter-well spaces and adjacent areas) under varying extraction pressures. Following a 180-day extraction period, the findings indicate a significant reduction in gas pressure by 83.9% for the extraction wells and the nearby areas, alongside a decrease in fracture network length by 10.94% and density by 5.04%. Compared to existing models for assessing multi-well CBM extraction, our interdisciplinary model demonstrates considerable analytical superiority. Notably, when the fractal parameters D_f and D_Tf, which characterize fracture density and tortuosity quantitatively, increase from 1.2 to 1.8, the residual gas pressure is reduced further by 11.6% and increased further by 3.9%, respectively.

多井开采是煤层气（CBM）回收项目中的普遍技术。尽管大量研究广泛探讨了井间距、多井泵送程度和井数等方面，但对井附近裂缝微观结构演化的动态（特别是井间区域）仍然没有充分了解其影响多井采矿项目。这项研究深入研究了煤层气采收工作中采用的多井开采方法，旨在阐明裂缝微观结构网络的发展。我们引入了一种新颖的跨学科综合研究框架，该框架将多井开采过程中观察到的多场耦合效应与分形理论相结合。该模型已经过验证，有助于检查多井开采时裂缝微演化的变化。此外，本研究还研究了不同抽采压力下敏感区域（即井间空间和邻近区域）内裂缝特征、煤层应力和煤层气压力的变化。经过 180 天的开采期后，研究结果表明，开采井和附近地区的气体压力显着降低了 83.9%，同时裂缝网络长度减少了 10.94%，密度减少了 5.04%。与评估多井煤层气开采的现有模型相比，我们的跨学科模型表现出相当大的分析优势。值得注意的是，当定量表征裂缝密度和曲折度的分形参数D _f和D _Tf从1.2增加到1.8时，残余气体压力分别进一步降低11.6%和增加3.9%。