In this article the possibility of methane gas extraction in coal deposits exploitation is considered. Experimental data on the application of hydrodynamic impact on a gas-saturated outburst coal seam prior to its baring in order to reduce gasdynamic activity due to an intensification of methane emission are presented. Also a structural and technological scheme of degassing pipelines that includes emergency protection and monitoring of coal mine methane parameters in real-time mode to ensure a safe, trouble-free process of its transportation to the cogeneration plant for further utilization is proposed.

The physics of hydrodynamic impact (HDI) is in the softening of the coal seam due to the generation of alternation stress in it. Stress is carried out due to injection and discharge of fluid into the coal seam in the filtration mode. The mathematical model of the processes occurring in the coal massif under HDI was developed. The model allows to determine the nature of the coal destruction in forward and inverse filtering of fluid in the massif. Cracking in the process of fluid filtration is achieved while simultaneously fulfilling two criteria: power and energy.

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Questions of numerical simulation of acoustic oscillations generation modes in the liquid flow around the groups of two and three circular cylinders are considered. In mining industry the processes of hydrodynamic impact on gas-saturated porous media produce significant acoustic emission both at the injection stage and at the liquid discharge stage. Simulation of such kind of acoustic processes is one of the actual problems of theoretical and applied fluid mechanics and under certain assumptions could be reduced to the flow around a group of bodies. Two approaches for numerical simulation of the acoustic oscillations generation induced by the flow around circular cylinders based on numerical solution of the Navier-Stokes equations for compressible and incompressible flows closed by differential model of turbulence and complemented by acoustic analogy equations have been developed. For laminar flows, eight different modes that fundamentally differ both in the flow structure and in the frequency spectrum of parameter oscillations have been identified. For turbulent flows, the classification criteria for the three main frequency modes are presented. Acoustic data are obtained using the Direct Noise Computation technology and acoustic analogies as well.