Study On The Gas Seepage Law In Gob And It's Numerical Simulation

Gob gas of fully mechanized caving face is one of the main part of the workplace gas emission. Gob gas drainage has been proved as a main technology that can guarantee safe production, this paper summarized the achievements of the study on the seepage law of gob gas of fully mechanized caving face, pointed out the gas seepage law of gob and cover rock is the basic theory to design an effective gas drainage system. Therefore, basic the similar material experiment and FLUENT numerical simulation, the failure characteristics of cover rock after mining and the gas seepage law in the gob and its cover rock are analyzed.The fluid dynamics and seepage mechanics are used to establish the equation of the gas seepage in gob. FLUENT is used to simulate 3 3D models of gas seepage in gob of fully mechanized caving face: 1. with air leakage only; 2. with air leakage and gas tail road; 3. with gas tail road and high level suction roadway. The conclusion are the gas tail road and high level suction roadway makes the high-concentration gas in the gob deliver to the drainage port, the distance of the air leakage go deep in the gob is increased too, so the result is the gas emission from the gob to the workplace reduced. Though the checking of field application in fully mechanized caving face 101 of a coal mine in Shan'Xi, the conclution is the numerical simulation fits in with the actual situation: a great quantity of gas is drained by gas tail road and high level suction roadway, the gas emission to the workplace is reduced, the safe production is achieved.