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The mechanism of promoting the autoignition of rich methanol-air mixtures by small additions of hydrogen peroxide has been studied using the tracer method. It has been shown that with the addition of hydrogen peroxide, the oxidation of methanol with atmospheric oxygen begins with the formation of hydroxyl from peroxide, followed by its interaction with methanol to form CH₃O, CH₂OH and then HO₂ and H₂O₂. The branching factor for hydroxyl is higher with the addition of peroxide higher with than without the addition of peroxide.

A promising direction in barrel ballistics to increase the muzzle velocity of a projectile is the use of new fuels as an attached charge. The paper presents an experimental and theoretical method for determining the law of fuel combustion in a manometric experiment (in a closed volume), which allows, by a small number of experiments, to determine the change in the law of combustion as the fuel burns and depending on pressure. The technique is demonstrated on the example of processing three experiments with model high-density fuel. The obtained laws of combustion of high-density fuels can later be used to calculate the gas-dynamic parameters of a shot from a barrel system or a nozzle bomb (in a semi-closed volume) using these fuels.

This paper presents a technique for non-contact diagnostics of on solid rocket motors (SRM) based on the analysis of acoustic vibrations generated by the supersonic jet of products combustion discharged from the nozzle. The combustor pressure in a model rocket motor fueled by E-5-0 solid propellant was determined experimentally by a non-invasive control method using a dynamic microphone located at a predetermined distance from the object of study and recording acoustic fields generated by the running engine. Experiments confirmed the possibility of non-contact determination of combustor pressure from the frequency of acoustic vibrations and the sound pressure generated by the jet of combustion products of the model SRM. Calculated pressures are in satisfactory agreement with the values recorded by intra-chamber pressure sensor.

Electrospark initiation of thermite mixtures based on nanosized powders of aluminum and copper oxide has been studied. Data on the effect of the energy of an electric spark discharge on the ignition delay have been obtained. When initiating long cylindrical samples of mixtures with a low-current spark, two types of unsteady combustion were observed. The first type is characterized by an exponential nature of the establishment of a constant burning rate. The second type is characterized by regions with incomplete reaction along the main direction of propagation. To obtain stationary modes of a thermite mixture with a minimum ignition delay time, it is necessary to use a discharge with energy of more than 5 mJ per 1 mm² mixture surface.

Experimental data are presented on the rate of pressure change during the combustion of an air suspension of coal dust in a closed spherical volume at various mass concentrations of coal dust. On the basis of the equations of mechanics of disperse media in a one-velocity one-temperature approximation, a physico-mathematical model for the combustion of an air suspension of coal dust in a closed spherical volume is formulated. The combustion wave propagation velocity relative to the gas suspension and the combustion velocity of a coal dust particle are model parameters and are determined by matching the calculation results with experimental data. Their agreement was good. The proposed approach can be used to assess the effect of coal dust combustion on the intensity of shock waves in coal mines during accidental methane explosions involving coal dust.

A pioneering study of the characteristics of combustion of liquid hydrocarbons in a superheated steam jet under conditions of a closed burner is performed by an example of the diesel fuel. An undated structure of an original low-power burner is presented. It is based on the principle of fuel atomization by a high-velocity steam jet and offers a possibility of controlling injection of primary and secondary air. Amounts of pollutants ejected into air are determined for different air-to-fuel ratios inside the burner. First comparisons of the developed burner with a production model of the liquid-fuel burner (Weishaupt burner) are performed. It is shown that addition of superheated steam ensures a high combustion efficiency and low contents of CO and NO_x in combustion products satisfying the most rigorous European standards.

Experiments are performed for studying the process of shock wave initiation of detonation in pure tetranitromethane and its mixtures with acetone, nitrobenzene, and methanol. Glowing of the detonation front is detected by high-speed cameras operating in slit scan and frame-by-frame modes. It is found that detonation both in pure tetranitromethane and in its mixtures with dilutants is initiated at localized sites. The number of these sites, the character of their formation, and the features of their growth and merging depend on the nature of dilutants. The evolution of the wave profiles is registered by a velocity interferometer system for any reflector (VISAR). The resultant velocity profiles are noticeably different from those predicted by the classical pattern of detonation initiation and evolution under a shock wave action.

The structures of detonation waves in mixtures of tetranitromethane with acetone was studied in experiments using a VISAR interferometer and a NANOGATE-22 electron-optical camera. At a diluent concentration of 10-40%, there was a sharp change in the flow in the reaction zone, manifested in a decrease in the amplitude of the von Newman spike up to its complete disappearance. Detonation waves are stable in almost the entire range of concentrations, except in the range near the limiting value of 52%. In approaching the limiting concentration, the waves become unstable, which is manifested in the formation of both the cellular structure of the front and reaction failure waves. The obtained experimental dependences of the detonation velocity on acetone concentration are in good agreement with thermodynamic calculations.

When using the method of multipoint initiation of the side surface of a cylindrical charge in a section perpendicular to the axis, a detonation wave with a complex gas-dynamic structure is formed, which has the shape of a polygon with vertices at the points of wave conjugation. The sides of the polygon are always convex towards the charge axis. To obtain a smooth cylindrical detonation wave with reverse curvature, it is proposed to use special devices at the points of initiation - lenses made of an inert material. The dynamic characteristics of the material are experimentally determined, and the method for constructing the lens profile is substantiated. Mathematical modeling of the operation of the node of initiation and formation of a cylindrical detonation wave in a charge has been carried out. The features of the operation of a single initiating node and a node that is part of the experimental assembly are shown. The dynamics of axisymmetric compression by a converging detonation wave is presented and compared with calculations.

The conditions of suppression of flame combustion and thermal decomposition in model forest and peat fires using water, foam concentrate emulsion (5%), bischofite solution (10%), FR-Les 01 solution (20%), flame retardant solution (vol. 5%), OS-5 solution (15%), and bentonite slurry (5%) were determined. Temperatures in the process of ignition of model fires and extinguishing of the latter by specialized water-based compositions were measured. Minimum volumes of the extinguishing compositions and the time necessary and sufficient to suppress the pyrolysis of plant biomass were established. Minimum irrigation densities of model forest and peat fires using water-based compositions with specialized additives were determined.