Research On The Distributing Gas Law In The Gob Area Based On Flow-tube Model

With the continuous extension of the depth of mining and the increase of mine intensification and the scale of mining, mine gas emission also increases, followed with the increasing gas hazard and accidents. And Gob air leakage is one of the most principal reasons that cause the working plane angle appearing the phenomenon of transfinite gas. This thesis simulates the gob flow field by virtue of the air leakage on the distribution calculation model base on network solution. Later, this thesis analyses the gas concentration field in Gob, and these analysis will offer the safe produce on coal face with the important monitoring data. With the analysis of the gas concentration distribute regular pattern, we know the gas emission source, migration and accumulation rule of mining discharging pressure gas, the diffusion movement rules and accumulation rules. At the same time, these rules and regular pattern will give the important ideas on the simulation with the Gob gas concentration field.The stream tube model originated in from1960s, and it is applied in the development of flow and oil and gas field. However, it is rarely seen to be applied in simulating the Gob gas concentration field. This thesis uses the explicit theory of the stream tube model, to build the solution formula with the known flow field in Gob. Meanwhile, we draw the flow line and flow field graph about the gas concentration field in Gob. Through the finite monitoring point, we can see the rules of the gas concentration distribution in Gob more directly.In the end, we apply the theories of Gob air leakage and stream tube model to one coal. And we get the flow field and the gas concentration field. The results show that the computation models of this thesis are correct and convenient.