Open AccessVerification of Rapid Determination of Coal Seam Permeability Coefficient Based on COMSOL
Author(s) -
Bingrui Li,
Shubo Li
Publication year - 2021
Publication title -
iop conference series. earth and environmental science
Language(s) - English
Resource type - Journals
eISSN - 1755-1307
pISSN - 1755-1315
DOI - 10.1088/1755-1315/647/1/012063
Subject(s) - permeability (electromagnetism) , coal , borehole , pressure drop , mechanics , coal mining , computer simulation , approximation error , materials science , mathematics , geology , geotechnical engineering , engineering , mathematical analysis , chemistry , physics , biochemistry , membrane , waste management
To verify the accuracy of the calculation method based on the indentation-pressure drop method to quickly determine the coal permeability coefficient, this paper simulated the gas pressure change curve of the borehole based on the COMSOL numerical simulation software. The pressure change curve obtained by setting different air permeability coefficients in the simulation software, combined with the rapid determination of the coal permeability coefficient calculation method to calculate the coal permeability coefficient, and the error between the simulated value and the calculated value is compared. The results show that the relative error between the simulated value and the calculated value is -23%~+45%, and the error between the calculated result and the simulated parameter is small, which verifies that the method of quickly determining the coal permeability coefficient based on the indentation-pressure drop method is correct and feasible. The simulation results show that the calculation results of the pressure curve obtained by the short-term simulation and the long-term simulation are basically the same. Therefore, the short-term measurement results can also be used to calculate the coal seam permeability coefficient. The rapid determination of the coal seam permeability coefficient is theoretically feasible.