THERMAL SCIENCE

International Scientific Journal

EXPERIMENTAL ANALYSIS AND MODEL STUDY ON EFFECTIVE STRESS SENSITIVITY OF COAL ROCK PERMEABILITY

ABSTRACT
Using the unsteady pressure drop method, permeability measurements of coal samples were conducted across various bedding directions under different effective stresses. Mercury injection, SEM, and micro-CT techniques were employed to analyze pore/fracture structures. By integrating experimental data, existing stress-sensitive permeability models were validated and refined. The results demonstrated that gas permeability in cores from different directions exponentially correlates with effective stress. During decompression, the permeability exhibited limited recovery and irreversible damage. Stress sensitivity assessments with varying parameters indicated high sensitivity of coal permeability to effective stress, both perpendicular and parallel to bedding planes. The revised permeability model predicts permeability with an error margin of less than 15%.
KEYWORDS
PAPER SUBMITTED: 2024-10-23
PAPER REVISED: 2024-11-26
PAPER ACCEPTED: 2024-12-05
PUBLISHED ONLINE: 2025-06-01
DOI REFERENCE: https://doi.org/10.2298/TSCI2502545B
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2025, VOLUME 29, ISSUE Issue 2, PAGES [1545 - 1550]
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2025 Society of Thermal Engineers of Serbia. Published by the VinĨa Institute of Nuclear Sciences, National Institute of the Republic of Serbia, Belgrade, Serbia. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International licence