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This paper presents a review of theoretical and experimental results obtained by Russian and international researchers over the past decades. The ice cover is modeled as an elastic plate. The primary focus is on the study of forced hydroelastic waves generated by dynamic loads acting on the floating elastic plate or by disturbances created by submerged sources in the fluid.

The paper presents the results of a study on erosive wear of polycrystalline diamond coatings deposited on a molybdenum substrate. Prior to deposition, the substrate surface was treated with a jet of micro-particles of either corundum or silicon carbide. The diamond coating was applied using a gas-jet deposition method from a H₂-CH₄-Ar mixture activated by a microwave discharge. It was found that preliminary surface treatment of the substrate increases the wear resistance of the resulting diamond coating.

The results of numerical modeling of electrophoresis of a single spherical ion-selective particle in a viscoelastic electrolyte are presented. The electrolyte behavior is described using the Oldroyd-B and FENE-CR fluid models. The study is limited to weak and moderate electric fields, corresponding to first-kind electrophoresis. The dependence of the electrophoretic velocity of the particle on polymer concentration and relaxation time is obtained.

The vector potential of the magnetic field is determined in the region between the inductor, the upper part of the floating zone, the liquid film, the feed rod, and the protective screen in an axisymmetric problem of crucible-free zone melting of a silicon sample with a radius of 5÷10 cm. The boundary condition at infinity is transferred to a semicircular arc connecting the feed rod to the protective screen and located at a sufficiently large distance from the inductor, which allows the problem to be considered in a finite domain. This domain is conformally mapped onto a rectangle, within which the problem of determining the magnetic field vector potential is solved. The problem is reduced to solving Laplace’s equation for the only non-zero component of the vector potential, A_φ , where φ is the polar angle, with first- or second-type boundary conditions on the edges of the rectangle. The method can be applied to calculate the variable thickness and shape of the liquid film adjacent to the lower part of the feed rod, as well as the hydrodynamic flow within it.

In a flow-through annular combustion chamber with a diameter of 503 mm, with a narrowed outlet section and profiling of the channel (installation of cavities at the beginning or end of the chamber), the modes of continuous multi-front detonation of kerosene with air heated to 800 K were implemented and investigated. It was shown that the installation of cavities increased the frequency of transverse waves. In the coordinates of the specific air consumption --- excess fuel coefficient, the region of implementation of detonation modes was determined. It was found that the existence of the continuous multi-front detonation mode is due to collisions of transverse shock waves generating transverse detonation waves, which degenerate into shock waves before collisions. When installing a cavern at the end of the annular cylindrical chamber, the maximum specific impulse relative to the fuel of 2,040 s was obtained. The minimum length of the combustion chamber in which the continuous multi-front detonation mode is implemented is in the range of 530 ÷ 670 mm. Measurements of pressure profile pulsation levels in the pre-chamber and at the combustion chamber outlet by high-frequency sensors have determined that they belong to the category of sound vibrations. This is important for the use of detonation combustion in practical applications.

The combustion of aluminum agglomerate particles with a diameter of 215 ÷ 840 μm in free fall in air at atmospheric pressure was investigated. Initially, spherically symmetric combustion is replaced by asymmetric combustion, fragmentation occurs; eventually, the combustion process ends with the formation of an oxide residue. The listed events are characterized by the corresponding time. In this article, the duration of the symmetric combustion stage is determined --- on average 0.5 ± 0.1 in relation to the combustion time. Empirical approximating dependences of the coordinate and velocity on time (x(t) and v(t)) for particles of different diameters are obtained. To perform analytical calculations of the motion of burning particles, the viscosity of air in the vicinity of the particle was chosen to be 6.98 10^-5 Pa · s, which corresponds to an average temperature of 2,005 K. By comparing the empirical and calculated dependencies x(t) and v(t), the effective aerodynamic drag coefficient of the particle was determined depending on its size in the form C_d(D, Re) = (9.33 + 0.13 D)/Re, where Re is the Reynolds number from the range 0.2 < Re < 5.2. For estimated calculations, C_d = 77/Re can be taken.

The energy capabilities of a hypothetical zwitterionic nitrohydrazine H₃N⁺N^-NO₂ as a component of artillery propellants are assessed. Compositions with a hydrocarbon binder, compared to standard propellant charges, allow increasing the muzzle energy of a projectile by ≈33% for a 152-mm howitzer and by ≈27% for a 125-mm tank gun without increasing the temperature of the propellant gases. For a 120-mm mortar, the increase in the muzzle energy of a mine is ≈14%. Similar compositions based on ammonium dinitramide are considered for comparison, which have shown lower efficiency. Compositions with an active binder also achieve high performance indicators. However, they have a high temperature of combustion products, which is unacceptable for most barrel systems.

TNT has several disadvantages, such as high vapor pressure, toxicity and viscosity. Explosives free from these disadvantages are being sought. In this paper, a new explosive, TNBA, 2,4,6-trinitro-3-bromoanisole, is synthesized by a chemical method. The thermal decomposition characteristics of TNBA are tested by DSC/TG-MS. The mechanical sensitivity, thermal sensitivity and detonation characteristics of TNBA and cast explosive based on it are estimated. The results show that the measured density of TNBA is 1.871 g/cm³. At a heating rate of 10 °C/min, the thermal decomposition peak of TNBA is observed at 287 °C, and H₂, C, CH₄, H₂O, CO, N₂, CO₂ and HBr gases are released. The peaks of CO and N₂ are the strongest. These results are similar to those calculated using NASA CEA2 software. The thermal sensitivity of TNBA is lower than that of TNT. The detonation velocity and heat of explosion of TNBA and TNBA-based cast explosive are similar to those of TNT. In particular, TNBA and its cast explosive have advantages in chemical energy reserve, performance, brisance, and the ability to accelerate metals.

Using high-frequency pressure sensors Kulite XTEH-10L-190 (M) Series, pressure profiles were recorded in a transverse detonation wave propagating in an annular cylindrical chamber during continuous spin detonation of a hydrogen--air mixture. The pressure levels in the detonation wave front, in the air collector, and at the chamber outlet were determined in relation to the average static pressure recorded by low-frequency sensors (10 kHz) from <<Trafag>>. Pressure oscillations behind the wave front indicate complex gas dynamics of the processes in its vicinity. A region of chemical reaction was revealed behind the wave front, comprising about 6.3% of the period between waves. A decrease in the minimum excess fuel coefficient was found with an increase in pressure in the combustion chamber to 0.22, at which continuous spin detonation develops. The velocities of transverse detonation waves decrease with decreasing fuel-excess ratio and in some modes approach the ideal Chapman-Jouguet detonation velocity. Based on the total and static pressure readings at the combustion chamber outlet, the specific impulse is calculated, the maximum value of which, minus cold outflow, is 5,000 s at a fuel-excess ratio of 0.35. It is shown that the total pressure loss during air outflow from the manifold into the combustion chamber through a 6 mm wide gap (critical outflow mode) is 4 ÷ 5% higher than during subcritical outflow through a 10 mm gap.

The effect of aluminum powder distribution on the explosion energy of layered composite charges of thermobaric explosives based on a melt of high-energy 3,4-dinitrofurosan furoxan (DNFT) was investigated. The composites consisted of inner and outer cylindrical layers with controlled spatial distribution of aluminum powder. Blast tests were carried out in a closed explosion chamber filled separately with either nitrogen or air. Data were obtained on the quasi-static pressure, excess pressure in the shock wave, and the evolution of the fireball. Using numerical modeling, the diffusion of aluminum powder during the explosion was studied using a combined discrete element and finite element method. The results show that concentrating aluminum powder in the outer layer of the composite increases the concentration of aluminum powder in the cloud, which leads to an increase in the burning rate and energy yield in the early stages of the explosion. Conversely, aluminum powder concentrated in the inner layer is compressed toward the center and then bounces back, slowing down diffusion and affecting anaerobic combustion processes.