Lin Fang^1,2,*, Mengjun Wu^1,2, Bin Wu³, Honglin Li⁴, Chenhao He^5,*, Fan Sun⁵

CMES-Computer Modeling in Engineering & Sciences, Vol.130, No.3, pp. 1649-1668, 2022, DOI:10.32604/cmes.2022.018527 - 30 December 2021

Abstract Based on the theories of the gas seepage in coal seams and the deformation of the coal-rock medium, the gas seepage field in coal-rock mass is coupled with the deformation field of the coal-rock mass to establish a fluid-structure interaction model for the interaction between coal gas and coal-rock masses. The outburst process in coal-rock masses under the joint action of gas pressure and crustal stress is simulated using the material point method. The simulation results show the changes in gas pressure, velocity distribution, maximum principal stress distribution, and damage distribution during the process of… More >

Haibo Liu^1,*, Yujie Dong², Fuzhong Wang¹

Energy Engineering, Vol.118, No.3, pp. 679-689, 2021, DOI:10.32604/EE.2021.014630 - 22 March 2021

Abstract For the problems of nonlinearity, uncertainty and low prediction accuracy in the gas outburst prediction of coal mining face, the least squares support vector machine (LSSVM) is proposed to establish the prediction model. Firstly, considering the inertia coefficients as global parameters lacks the ability to improve the solution for the traditional particle swarm optimization (PSO), an improved PSO (IPSO) algorithm is introduced to adjust different inertia weights in updating the particle swarm and solve the fitness to stagnate. Secondly, the penalty factor and kernel function parameter of LSSVM are searched automatically, and the regression accuracy More >

Jianguo Zhang¹, Biao Hu^2,*, Xiyuan Li¹, Hongxing Zhou², Zhixu Dai³, Yanlei Lu³, Deyang Wang²

Energy Engineering, Vol.118, No.3, pp. 605-614, 2021, DOI:10.32604/EE.2021.014655 - 22 March 2021

Abstract To accurately predict the risk of coal and gas outburst and evaluate the reliability of desorption indexes of drilling cuttings (K₁ and ∆h₂) in No. 16 coal seam of Pingmei No. 12 coal mine, two sets of coal samples were selected from the target coal seams for proximate analyses, methane adsorption/desorption tests, and desorption indexes of drilling cuttings tests. The results indicated that the desorption volume in the initial stage of desorption is large, and increases slowly in the later stage. The methane desorption volume of PMD1 and PMD2 coal samples accounts for 15.14%–18.09% and 15.72%–18.17%… More >

Yi Xue^1,2,3

CMES-Computer Modeling in Engineering & Sciences, Vol.113, No.4, pp. 429-441, 2017, DOI:10.3970/cmes.2017.113.429

Abstract The lack of research on the effect of diffusion on methane extraction leads to low methane concentration and low utilization. The Comsol Multiphysics software is used to solve the numerical gas and solid coupled model which considers the diffusion of coal matrix, fracture seepage, permeability evolution and coal deformation. The simulation results reveal the effect of diffusion process on methane migration. The gas diffusion rate is relatively high in the initial stage. With the increase in time, the difference between coal fractures and coal matrix blocks becomes lower and the gas diffusion rate decreases gradually. More >