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This paper describes different types of modern magneto-cumulative generators, their operating principles, design, and main characteristics. Application areas of the generators for fundamental and applied studies in high-energy density physics are considered. Some investigation results are presented. Prospects for the further development of the MCG facilities designed in VNIIEF are discussed.

The energy capabilities of acceleration devices are theoretically analyzed, including various ramjet-in-tube options for gas-dynamic acceleration of massive (1 to 40 kg) bodies under ground conditions up to velocities of 2-3 km/s. Simple quasi-one-dimensional models for a perfect gas are used in the computations. It is demonstrated that the use of a ramjet-in-tube with a closed exit allows the velocities of acceleration of massive bodies to be increased to 3 km/s, which is twice greater than the values that can be obtained with available gunpowder-based methods.

The limiting possibilities and energy efficiency of single-stage acceleration of solid by compressed gas in a pipe (ballistic Lagrange problem) is under study. An exact partial solution of the ballistic Lagrange problem in a homogeneous deformation approximation is obtained. The calculation results are compared by different methods with the experimental data and the calculation results from other papers. It is shown that using an efficiency coefficient as a criterion for choosing an optimal solution prevents from using the effective configurations of ballistic devices.

The influence of a sudden change in the external magnetic field on the flow of an electrically conducting Bingham fluid in a two-dimensional channel is considered. It is demonstrated that a method of independent descriptions of the flow in plastic and viscous regions can be used for studying magnetohydrodynamic flows of the Bingham fluid. An exact equation is derived for the position of the plastic flow region boundary as a function of time and magnetic field induction. It is shown that the corresponding Cauchy problem has a unique asymptotically stable solution. Results of numerical integration for some values of parameters are presented; these result confirm the qualitative conclusions.

Results of direct numerical simulations of the roughness-induced development of instability and transition to turbulence in a supersonic boundary layer on a blunted cone for the free-stream Mach number M¥ = 5.95 are presented. The flow parameters and model geometry are consistent with the conditions of the experiments performed in the study. The following roughness types are considered: random distributed roughness, individual roughness elements of different shapes, and a group of regularly arranged roughness elements. The processes of the instability development and transition for different roughness types are compared, and possible mechanisms of the roughness influence on the stability of boundary layers on blunted bodies are discussed.

This paper presents the results of an analysis of field measurements of a wave bore in the pycnocline of a shallow sea using vertical located thermistors. Hydrodynamic interpretation of the space-time structure of the bore is performed using a mathematical model of a weakly dispersed shallow sea which takes into account the influence of cubic nonlinearity and low-frequency dispersion. The limiting amplitude and minimum duration of the soliton solutions of the model are determined. An algorithm for evaluating these parameters based on measurements of the pulsations of isotherms induced by the bore is proposed. The limiting amplitude and minimum duration of solitary waves in the pycnocline in the coastal the Sea of Japan are evaluated.

The problem of waves generated in a fluid and an ice sheet by a pressure region moving on the free surface of the fluid along the edge of the semi-infinite ice sheet was solved using the Wiener-Hopf method. The load applied in some region simulates an air cushion vehicle, and the ice sheet is modeled by a thin elastic plate of constant thickness on the surface of an ideal incompressible fluid of finite depth. In a moving coordinate system, the plate deflection and the fluid elevation are assumed to be steady. The wave forces, the elevation the free surface of the fluid, the deflection and deformation of the plate at various speeds of the load were investigated. It has been found that at near-critical load speeds, the ice sheet has a significant effect on the wave forces (wave resistance and side force) acting on the body moving on the free surface, and this effect is most pronounced at small distances from the edge. It has been shown that for some values of the speed, ice thickness, and load pressure, breaking of the ice sheet near the edge is possible.

The combustion of Al/B agglomerates (0.81/0.19) with a diameter of 320-780 m in free fall in air was first studied by the method of model monodisperse agglomerates method. The dependence of the burning time on size was determined. Burning residue particles were subjected to morphological, chemical, mass, particle size, and elemental (EDS method) analyses. It has been found that the essential features of the combustion mechanism of Al/B agglomerates compared to aluminum are long combustion; the specific core-shell structure of the particles, with boron present in the core and absent in the shell; a slight change in mass and diameter of particles during combustion.

The achievement of stable colloidal suspensions of reactive metal powders in liquid propellants is crucial for obtaining enhanced thrust per unit mass. Aluminium is of interest due to its availability, stability, and high combustion enthalpy (32000 J/g). In this manuscript, ultrafine spherical aluminium particles with the average size of 15 m are produced by wet milling. Aluminium particles are effectively surface-modified with a polymeric surfactant and sterically stabilized in an organic solvent (toluene). Organically modified aluminium demonstrates a drastic change in surface properties from hydrophilic to hydrophobic, with effective transfer from the aqueous to organic phase. The stabilized particles are effectively dispersed in a liquid rocket propellant (hydrazine). The impact of aluminium particles on hydrazine combustion characteristics is evaluated by using a thermodynamic code named ICT (Institute of Chemical Technology in Germany, 2008). Aluminium particles offer an increase in the combustion temperature, oxygen balance, characteristic exhaust velocity, and specific impulse. The optimum solid loading level of aluminium in the hydrazine fuel is found to be 6 wt%.

By considering the parametric variation of an individual boron particle in a boron agglomerate, the heat transfer, and the mass transfer between the boron particle agglomerate and the surroundings, an ignition and combustion model of a boron agglomerate is proposed. An experiment of a ramjet combustor using a boron-based slurry fuel is designed and operated for the purpose of validating the ramjet configuration and verifying the combustion of boron particles. Then a mathematical model for simulating a multiphase reacting flow within the combustor of a boron-based slurry fuel ramjet is established. Kerosene droplets and boron particles are injected discretely to the burner flowfield, and their trajectories are traced using the discrete phase model. The influence of the agglomerate size, bypass air mass flow rate, initial boron particle diameter, and boron particle content on the combustion efficiency of the slurry fuels is analyzed in detail. The results show that the combustion efficiency decreases with an increase in the agglomerate radius, initial boron particle diameter, and boron particle content. The combustion efficiency increases with an increase in the mass flow rate of bypass air. If the agglomerate diameter is greater than 100 m or the bypass air mass flow rate is smaller than 50 g/s, the boron particles cannot be fully burned.