The aim of the study was to develop methods to reduce the penetration ability of the flame front and red-hot striking elements that propagate in the confined space of mines. In the article is considered a method for localizing explosions of a methane-dust mixture in coal mines, by creating an aqueous barrier (increased density) in the propagation path of the flame front and incandescent particles, using a high-energy pyrotechnic composition based on nanoaluminum. The optimal pyrotechnic composition contents of ammonium nitrate - 50%, smokeless powder - 45%, magnesium - 3% and nanoaluminum - 2%. This composition punched the target to a depth of 6.5 mm with a barrier thickness of 50 mm. Water cannon with a nozzle with a diameter of 80mm, allows to localize the spread of the flame front.
The purpose of this study is the development and investigation of gas-generating composition based on potassium chlorate for the destruction of a stone. The thermodynamic analysis of the energy characteristics of the studied gasgenerating compositions was carried out. Influence of various amounts of nano-aluminium on features and regularities of burning and ignition of pyrotechnic gas-generating composition on the basis of potassium chlorate was studied. By results of thermodynamic calculation and experimental work the optimum gas-generating composition for destruction of a stone -KClO3-72 %, polyethylene -17%, nano -aluminium Alex-11% was chosen. The carried-out polygon tests on the destruction of a stone had shown high efficiency of use of this gas-generating composition for destruction of a stone.
Considering the blow force as the given parameter during the combustion of pyrotechnic compositions, it is possible to calculate the mass of a necessary charge of pyrotechnic formulation. By this cause, a special interest is the model of an explosion or burning of the pyrotechnic composition, in which is possible at high degree of accuracy to calculate the mass of the pyrotechnic charge. This will lower the percentage of accidents when dealing with pyrotechnics. The aim of the work is formulation of the physical and mathematical model of explosion or combustion of pyrotechnic composition on the basis of laws of conservation of momentum and energy. The calculation formulas were checked on a concrete example-pyroxylin and compared with data from reference books and the Internet. The analysis of a calculated formula for a pyroxylin showed that in the course of explosion the main contribution to destruction of the chosen objects is made by a potential energy of gases (about 88%), and only 12% by a kinetic energy of incandescent gases, but when calculating force of explosion it needs to be considered.
This work is devoted to the development of pyrotechnic delay mixtures from a titanium matrix reinforced with carbon nanotubes using a combination of preliminary mechanical activation and thermal explosion. The phase and structural transformations of the Ti-CNTs mixtures were analyzed by microscopy and X-ray diffraction. The combustion temperature is practically independent of pressure, it remains constant over the entire range of argon pressure. These delay compositions are not sensitive to different mechanical influences. It is proved that certain amount of CNTs added to delay composition can increase delay precision and further doing so achieved less temperature dependence. The retardant compositions BaCrO4 + Ti / CNT containing carbon nanotubes have the improved characteristics of the retardant composition, such as delay accuracy, combustion stability. The developed retarding compositions are safe in production and at all stages of circulation.
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