Effect of Pendulum Waves from Earthquakes on Gas-Dynamic Behavior of Coal Seams in Kuzbass

The paper represents the results of monitoring and evaluation of the efficiency of hydroimpulsive disintegration of outburst-prone coal seams in the stopes of development mine workings using a system of sound detecting facilities. Methods of acoustic emission control have been considered as well as the monitoring tasks to evaluate rock mass conditions before the procedure and after it inclusive of the results of sound accompaniment of hydraulic disintegration of the coal seam. It has been determined that the higher concentration of stresses within the rock mass is, the more efficient action of high frequency self-oscillations of cavitation transmitter is on both the fissuring and changes in gas-dynamic state of the coal seam. It has been recommended to apply a mode of impulsive fluid pumping under the conditions where coal seam is in the stress-strain state.

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CALIBRATION COEFFICIENTS OF CONNECTION BETWEEN THE LANGMUIR ADSORPTION EQUATION AND V.N. OPARINA’S KINEMATIC EXPRESSION FOR PENDULUM-TYPE WAVES ACCORDING TO LOCAL MEASUREMENTS AT THE COAL DEPOSITS OF KUZBASS

Interexpo GEO-Siberia ◽

10.33764/2618-981x-2021-2-4-3-13 ◽

2021 ◽

Vol 2 (4) ◽

pp. 3-13

Author(s):

Viktor N. Oparin ◽

Tatiana A. Kiryaeva

Keyword(s):

Field Experiments ◽

Structural Parameter ◽

Coal Seams ◽

Pendulum Waves ◽

Translational Movement ◽

Adsorption Equation ◽

Coal Deposits ◽

Local Measurements ◽

The Relationship ◽

Calibration Coefficients

The article shows that at present there are experimental and theoretical prerequisites for establishing formalized relationships between deformation-wave and physicochemical processes occurring in real multiphase rock massifs. The calibration coefficients of the relationship in the correspondence operator between the adsorption equation and the kinematic expression for pendulum waves were established, verified in comparison with the available measurements in laboratory and field experiments for coals of the entire metamorphic series: quantitative values of the physicochemical invariant were determined for coals of different stages of metamorphism and structural parameter of the geomedium, as well as the velocity of propagation of a longitudinal wave in geoblocks-carriers of pendulum waves and translational movement of "colliding" geoblocks for different stages of metamorphism. It is shown that the values of the obtained dispersion allow one to take into account all the variety of the main stages of metamorphism of Kuzbass coal deposits in the theory and forecast of outburst hazard, i.e. take into account the real qualities of coal seams.

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Numerical determination of the gas-dynamic behavior of vane cascades with various deflection angles of the trailing edges of longitudinal ribs of an advanced gas-turbine engine thrust reverser

Russian Aeronautics ◽

10.3103/s1068799817020076 ◽

2017 ◽

Vol 60 (2) ◽

pp. 206-213

Author(s):

V. L. Varsegov ◽

A. S. Shabalin

Keyword(s):

Gas Turbine ◽

Dynamic Behavior ◽

Numerical Determination ◽

Turbine Engine ◽

Longitudinal Ribs ◽

Engine Thrust ◽

Gas Dynamic ◽

Trailing Edges ◽

Thrust Reverser

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Room-and-pillar mining of thick coal seams in the conditions of high gas dynamic hazard in Kuzbass

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/262/1/012064 ◽

2019 ◽

Vol 262 ◽

pp. 012064

Author(s):

VV Sementsov ◽

SA Prokopenko

Keyword(s):

Coal Seams ◽

Room And Pillar Mining ◽

Gas Dynamic ◽

Pillar Mining

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Methane gas hydrates influence on sudden coal and gas outbursts during underground mining of coal deposits

E3S Web of Conferences ◽

10.1051/e3sconf/202020101002 ◽

2020 ◽

Vol 201 ◽

pp. 01002

Author(s):

Volodymyr Bondarenko ◽

Olena Svietkina ◽

Roman Lysenko ◽

Baochang Liu

Keyword(s):

Gas Hydrates ◽

Gas Hydrate ◽

Underground Mining ◽

Coal Seams ◽

Dynamic Activity ◽

Gas Dynamic ◽

Coal Deposits ◽

Thermobaric Conditions ◽

Coal And Gas Outbursts ◽

Methane Gas Hydrates

The mechanism of gas hydrates formation in coal seams is studied in the paper, as well as their involvement is hypothesized in the sudden outbursts of coal and gas during underground mining of coal deposits. It has been substantiated and proved that one of the real reasons for subsequent outbursts is the formation of gas hydrates in coal as a type of secondary gas hydrate deposits. It has been also substantiated that, as a result of coal metamorphism, a large amount of gaseous hydrocarbons, mainly methane, is formed in the seam, which under certain thermobaric conditions leads to the gas hydrates formation. It has been experimentally proved that the mechanism of such inclusions formation between gas hydrate and coal is a result of strong chemisorption, which, when disturbing thermobaric conditions, leads to gas-dynamic activity of coal seams. It has been revealed that during the dissociation of gas hydrates, obtained in a medium of activated coals, twice as much gaseous methane is released. The research analysis indicates that the formation of natural gas solid solutions in coal pores under certain thermodynamic conditions and the natural humidity, characteristic of coal seams, is one of the causes of sudden coal and gas outbursts. The gas hydrates dissociation influences on the gas-dynamic activity of a coal seam and the formation of an outburst hazardous situation.

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