Study On The Numerical Simulation Of Gas Control In The Goaf Of High-Gas And Full-Mechanized Mine

Fluid Dynamics in Porous Media, Heat and Mass Transfer and Numerical Methods theory and so on are used in the research. The velocity field,the pressure field, and the concentration field for the flow in the god are studied. According to the characters of the collapsed rocks in the gob of 103-working face in Tianchi Coal Mine, the characteristics of porosity distribution in gob are studied, the characteristic of elliptical-typed distribution of permeability coefficient is proposed. Based on mass conservation, momentum conservation and species conservation law, combined with flow pattern in gob, a general mathematical model of gas flow is derived under the different flow. For gob sharp and gas flow mathematical model, the calculating area, gas flow equations and boundary conditions are dispersed by finite volume method and the dispersed equations are solved by SIMPLE algorithm. Using commercial CFD software (Fluent), the gob is simulated, the gas and oxygen concentration are obtained though Tailgate gas discharge, the results are in good agreement with the measured data. By blocking the gas tailgate and regulating the wind of the Inlet Lane, the gob is simulated to obtain the concentration of the gas, this result shows only by increasing air flow to solve the corner gas gauge and Air Leakage serious problem is impossible. Though Tailgate gas discharge the distribution of gas concentration are simulated under different wind amount, to determine a reasonable wind amount, to ensure that the upper-corner gas concentration is less than 1%. By taking tailgate gas discharge and adjusting air flow, the upper-corner gas gauge is solved.