Study on gas seepage-diffusion law and numerical simulation in goaf
Cui Chongbin
Yuan Jiguang
Qu Hu
Chen Qiaojun
Wang Zhaoqian
Cao Mingliang
Abstract：Gas emission in goaf is one of the key issues in coal mine safety production,and the study of its laws is of great significance for gas control and resource utilization.Accurately describing the characteristics of gas migration is challenging due to the heterogeneity of goaf,the complexity of fracture networks,and the coupling of multiple factors.Therefore,taking the No.4304 working face of Malan Coal Mine as the research object,a porosity model of goaf was constructed based on the key strata theory and the distribution character-istics of"O"-ring.Combined with the seepage-diffusion mathematical model,COMSOL Multiphysics software was used to numerically simulate the gas emission process in goaf.The influence of inlet air velocity,recovery rate,and initial gas desorption rate on gas emission was systematically analyzed.The research results show that the gas concentration in the goaf gradually increases along the direction,and the gas concentration on the return air side is significantly higher than that on the inlet air side.The gas concentration is the highest at the open-off cut of the return air side,reaching 68.04%,and the gas emission rate is 3.637 5 m3/min.The research results provide a theoretical basis for gas control in goaf areas.
Keywords：gas emissionnumerical simulationsimilar experimentdistribution of"O"-ringmathematical model
Publication Date：2025-08-25
Online Publishing Date：2025-09-12(First online date of this platform, not the publication date of the document)
Pages：8( 1-8 )