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An approach to determining the degree of decomposition of plasticized octogen at different ambient temperatures is presented. A scheme of works aimed at determining the temperature-time conditions of accelerated aging of plasticized octogen and establishing guaranteed periods of storage and operation of plasticized octogen is proposed. For calculations, a model of kinetics of slow decomposition of the studied explosive substance, constructed on the basis of heat release data obtained by differential scanning calorimetry, is used. The application of the presented model allows to estimate the shelf life and operation of explosive substances based on the degree of decomposition indicator.

A new empirical method for predicting detonation pressure of various types of organic and inorganic explosives is presented. The method identifies detonation products by the product that releases the maximum amount of heat per oxygen atom. The proposed model provides accurate and reliable estimates of detonation products compared to existing models. Using these identified products, detonation parameters such as the number of moles of gaseous products, their average molecular weight, and the maximum heat of detonation are calculated. A power-law relationship is established between the detonation parameter and experimental values of detonation pressure for different explosives. Unlike other models, the detonation pressure calculated by the new model agrees well with the experimental values for organic and inorganic explosives. These results indicate that detonation pressure predictions based on the new model are simple, accurate, and more reliable than those based on existing models, thereby contributing to the development of environmentally friendly, high-performance explosives.

Experiments and numerical modeling of the jet formation process and target penetration characteristics by micro-cumulative charges with polymer liners were conducted. The influence of the liner material, the distance from the charge to the target and its structure on the operation of the cumulative charge was analyzed. The results show that, compared to a copper jet, the penetration depth of the polymer jet decreased, and the crater diameter during penetration increased.

As a typical non-cylindrical structure, the prismatic shell with semi-finished fragments is extremely important for the structural design and evaluation of the destruction efficiency of the innovative warhead. The velocity and scattering angles of fragments are important parameters in the creation of the warhead and protective elements. However, the vast majority of existing formulas for the fragment velocity are created specifically for the cylindrical body, and there are very few formulas for calculating the scattering angle as applied to the prismatic body. In this paper, using theoretical analysis, a formula for the fragment velocity from the prismatic body is derived, and equations for both the radial and axial scattering angles of fragments are proposed. The rationality of the formulas was confirmed by experimentally verified numerical results. Ultimately, based on the obtained expressions and orthogonal analysis, the laws of influence of dimensionless geometric parameters on the scattering angle and specific kinetic energy of fragments were established, and the primary and secondary orders of influence of each parameter on the scattering angle and specific kinetic energy were determined, respectively. The results of this work will form the basis for further research into prismatic metal shells and other types of asymmetric shells, as well as a reliable source for the technical design of innovative warheads.

Most interesting and important gas-dynamic and kinetic parameters of combustion, explosion and detonation of the combustible ammonia/oxygen system in the range from the lower to the upper concentration limit with a change in the initial pressure and temperature are presented. From the point of view of explosion safety, the most important data are on the critical initiation energy, which allows analyzing the relative danger of various mixtures. Critical energy is defined as the minimum energy of the initiator that ensures the propagation of combustion and detonation waves in the mixture under study: the lower the critical initiation energy, the more dangerous the mixture.

The paper presents the results of a study of the effect of methane dilution with hydrogen on the electrochemical properties of the flame. Both diffusion flames and combustion of a premixed mixture in a Bunsen burner were considered. It was found that for mixtures with a molar fraction of methane in the fuel of more than 40%, the electric current linearly depends on the amount of methane. When the molar fraction of methane in the mixture is less than 40%, the dependence becomes nonlinear. The transition boundary from linear to nonlinear relationship between the magnitude of the flowing current and the amount of methane in the fuel mixture does not depend on the flow rate, the shape of the electrodes, and the combustion mode (diffusion, premixed fuel-air mixture). Registration of the chemiluminescence of the CH* radical demonstrates a similar dependence of the flame glow intensity on the volume fraction of methane in the fuel.

The results of an experimental study of initiation of hydrogen combustion in a supersonic flow with fuel supply from the channel wall are presented. Data are obtained on the dynamics of disturbance development from gas-dynamic pulses and on the transition to the combustion mode in a pseudo-shock, when fuel is supplied from the combustion chamber walls rather than along the flow axis. Features of pre-detonation combustion initiation for such a scheme of hydrogen supply to a supersonic flow are revealed. It is shown that the steady-state modes of pre-detonation combustion slightly differ depending on the fuel supply method (along the axis or from the flow periphery), while the dynamics of wave structure propagation from gas-dynamic pulses is almost identical in both cases.

The paper presents the results of pyrolysis of tableted microparticles (1 g/cm³) of brown, long-flame gas, gas, fat and coke coals in an argon environment under the action of laser pulses (1064 nm, 12 ns, 6 Hz, 0.2 ÷ 0.5 J/cm²), which results in a number of nonlinear processes: 1) ablation of explosive samples with the emission of microparticles of 10 ÷ 60 μm in size upon reaching a radiation energy density of 0.1 ÷ 0.2 J/cm²; 2) optical breakdown localized on microprotrusions on the surface of coal particles, evaporation of microprotrusions and deposition of a thin film of amorphous carbon on the reactor walls; 3) initiation of thermochemical reactions in the breakdown channels, leading to the release of gaseous products, the concentration of which nonlinearly increases with an increase in the energy density of laser pulses. Molecular gases H₂, CH₄, C₂H₂, CO, CO₂ were registered. Dependences of the composition of gaseous products of coal pyrolysis on their technical and genetic characteristics were established.

The possibility of synthesizing metal ceramics from a powder and granulated mixture of (100 - X)(Ti + C) + XMe, X = 0 ÷ 30 % (wt.), was tested by replacing nichrome Me = X20H80 with a mixture of Ni and Cr metal powders for granules of 0.6 and 1.7 mm in size. The experiments were carried out with impurity gases filtered in the direction of the combustion front or removed through the side surface of the sample. Quantitative estimates of the impurity gas content in the studied mixtures were obtained, which satisfactorily explained the experimental combustion rate of the granulated mixtures. The calculation results showed that a safe conductive combustion mode was observed for all compositions with 0.6 mm granules. For a batch of 1.7 mm granules, combustion occurred in the convective mode at X < 10 % (a bundle of Ni and Cr) and at X < 20 % (a bundle of nichrome). The results of X-ray phase analysis showed the identity of the phase composition of combustion products when replacing nichrome powder with a mixture of Ni and Cr powders with the same dilution with a metal binder X and the absence of side phases.

The propagation of a detonation wave in narrow flat and square channels is numerically simulated. The processes of instability development of a plane detonation wave and formation of a non-stationary multi-front structure are studied, the features of this process in two-dimensional and three-dimensional cases are considered. It is shown that in a flat channel the growth of transverse disturbances leads to the formation of a cellular structure first with small, then with larger cells. In a square channel the so-called diagonal three-dimensional structure is formed, which, however, is eventually replaced by the spin detonation mode. Its characteristics are studied, the spin step value is estimated. Good agreement with the predictions of the acoustic theory is shown.