Nalisko N.N. How to determine safety distance at emergency atmospheric explosions in the blind drifts in view of reflection of shock air waves

 

Geoteh. meh. 2016, 127, 112-126

 HOW TO DETERMINE SAFETY DISTANCE AT EMERGENCY ATMOSPHERICEXPLOSIONS IN THE BLIND DRIFTS IN VIEW OF REFLECTIONOF SHOCK AIR WAVES

1Nalisko N.N.

1SHEI «PSACEA» 

UDC 331.452:519.6: 622.81 

Abstract. To increase the accuracy of calculation of safety distances when a gas explosion at the damaged sections of coal mines were carried out numerical simulations using a mathematical model of the shock tube to spread shock waves of air in cylindrical channels. Shock waves generated by explosion elongated gas-filled clouds are stretches of canals. We studied the patterns of distribution of the air shock wave front in the explosion near the bottom of deadlock. It is shown as a dynamic pressure change, speed, density and temperature of the gas flow generation along the axis. It was found that the effect of the shock wave reflection from the bottom plane can increase the amplitude of the bow wave of up to 36 % (for typical sections of mines), power pulse wave generated by up to 70%. The maximum distance from the scene of the explosion to the face in which there are noticeable ripple effects is 180 m. Regularities of changes in the degree of intensity of the shock wave and the distance to the point of confluence of reflected and head waves, depending on the initial conditions. The regularities presented in graphs and regression equations. The method of accounting effects of shock wave of air waves in calculating safe distances.
Keywords: air shock wave, a ripple effect, dead-end mine workings, reflection, wave intensity, numerical calculation.

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About the author:

Nalisko Nikolay Nikolaevich, Candidate of Technical Sciences (Ph.D), Associate Professor of the Department of Life Safety, Pridneprovsk State Academy of Civil Engineering and Architecture (PSACEA), Dnepropetrovsk, Ukraine, This email address is being protected from spambots. You need JavaScript enabled to view it. .