Interdisciplinary approaches to modeling extraction efficiency and safety for clean energy under coupled multi-field effects

Abstract

Coal bed methane, a crucial clean energy source, has attracted extensive research attention. Characterized by intricate and rough fracture systems, coal seam is vital for gas migration, which will be influenced by the in situ stress, coal temperature, adsorption–desorption effect, solid deformation, and gas pressure. This paper introduces an innovative, interdisciplinary fractal model that addresses the limitations of current computational models in accurately representing the complex fractures under the coupled multi-field effects. Four novel fractal micro-parameters are introduced to capture the dynamics of rough networks. And rigorous validation against field extraction data reveals that the proposed micro-parameters outperform existing methods in analytical efficacy. Notably, those micro-parameters significantly influence fracture behavior and gas seepage. For instance, a DT increase from 1.2 to 1.8 and an ε rise from 0.06 to 0.18 lead to a respective 29.8% and 22.7% increase in gas pressure. Moreover, alterations in these fractal micro-parameters under coupled multi-field effects markedly impact coal bed stress, raising safety concerns in engineering projects, with a potential increase in coal stress by up to 2.62%. This research offers innovative insights into the complex coupled mechanisms governing rough fractures and significantly advances the understanding of the efficiency and safety in clean energy extraction processes.