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The results of the numerical modeling of the flow over configurations consisting of two adjacent wedges with swept leading edges located on a flat surface of the pre-compression ramp are presented. The flow around compression wedges with different sweeps of leading edges is considered: zero sweep (χ = 0), positive sweep (χ > 0), and negative sweep (χ < 0). Swept wedges deflect the flows compressed by them either to the sides opposite to the configuration symmetry plane (χ > 0) or, on contrary, one towards another (χ < 0). The computations have been done with solution of the averaged Navier—Stokes equations and with the use of the SST κ-ω turbulence model at the freestream Mach number М = 6. The difference in flow structure is analyzed, which includes, in particular, quasi-conical three-dimensional separations of the turbulent boundary layer on the pre-compression surface, which are induced by shock waves generated by swept wedges. The characteristics of the side flow spread on compression wedges of different sweep are presented.

Results of an experimental study of the evolution of short-duration isolated wave packets in flat-plate boundary layer at Mach number M = 2 are reported. The influence of the wave packets on the laminar-turbulent transition onset is examined. Interaction of the wave packets with natural disturbances is studied. The spatio-wave structure of the wave packets is investigated in detail. The spreading angle of the wave pack-ets and their propagation velocities are evaluated.

A 3D turbulent separated flow in the neighborhood of a plate-mounted bluff body, a parallelepiped with side length ratio 1:1:2, has been numerically simulated. The 3D structure of the flow in the vicinity of the body was revealed, and the distributions of flow quantities were obtained. Numerical data for the 3D separated flow obtained with the help of several turbulence models were compared to experimental data on the profiles of mean flow velocity and turbulence kinetic energy. It is shown that restriction of the production term for turbulence kinetic energy allows a reduction in turbulence viscosity level and improves the prediction accuracy for separation zones.

A semi-empirical model of the hydrodiode is considered. The model is based on the balance equation for the liquid flow across a two-membrane hydrodiode. Results of the quantitative study are compared to experimental data.

Results of the numerical study of hydrodynamics and heat transfer in a laminar flow of viscoelastic fluid in a flat slot channel are presented in the present paper. The model of nonlinear viscoelastic fluid of Phan-Thien—Tanner is used to describe the viscoelastic properties of fluid. The solution to the stated problem by software package “COMSOL Multiphysics” is considered. The method of solution is verified, and results are compared with data of the other authors. It is determined that in the flow of viscoelastic fluid in a flat slot channel, the maximal contribution of heating due to dissipation is approximately 7–8 %.

The paper presents the results of testing a methodology for calculating two-phase flows in mini- and microchannels. The numerical methodology is based on the known fluid-in-cell method (VOF method) and the CSF procedure to account for surface tension forces. Solutions of several test problems of two-phase flow in microchannels, including the water-oil emulsion flow and gas-liquid flow in microchannels of the T-type and the stationary slug flow in a circular minichannel, were considered with the aid of this technique. Comparisons of numerical results with experimental data were carried out. A good agreement between the results was obtained.

Systematic experimental and computational studies of the energy efficiency of continuous-detonation combustors (CDCs) have been performed. A small-size and a large-size CDCs using hydrogen as fuel and oxygen or air as oxidizer have been developed and tested. It was first experimentally proved that the Zel'dovich thermodynamic cycle with continuous-detonation combustion of a hydrogen-oxygen mixture in an annular combustor is more efficient than the Brayton thermodynamic cycle with continuous combustion of the mixture, other things being equal. The specific impulse of a small-size bench-scale rocket engine with a 50 mm diameter CDC operating in the continuous-detonation mode was 6–7% higher than that in the continuous combustion mode of operation. The measured fuel specific impulse for the large-size CDC of 406 mm diameter running on a hydrogen-air mixture was at a level of 3000 s. Three-dimensional calculations to optimize the structure and operation mode of the large-size CDC have shown that when running on a combustible mixture with a nearly stoichiometric integral composition, the specific impulse can be increased to »4200 s.

A special facility for investigating gaseous detonation was designed using a CCDS2000 computerized detonation-spraying complex to implement flow-through supply of the components of an explosive mixture and activation of deflagration-to-detonation transition in a long cylindrical channel. The detonation velocity and the cell size of the detonation front in mixtures of a composite fuel based on methyl acetylene and allene with oxygen were experimentally determined, and the concentration limits of steady-state detonation in a tube of 26 mm diameter were obtained. Detonation parameters were calculated and compared with experimental values. For comparison, the detonation of mixtures of acetylene and propane-butane with oxygen under similar conditions was studied.

The main results of years of research of metal dust flames aimed at the development of the scientific basis for the method of gas-disperse synthesis of metal oxide nanopowders are discussed. Methods of burning metal dust in oxide-containing media, the key problems of gas-disperse synthesis, and possible ways to solve these problems are considered. The ways of controlling the disperse composition of vapor-phase and gas-phase combustion products of metal particles by variation of the macroparameters of the dust flame and ionization of condensed and gaseous phases in the combustion zone with the help of adding easily ionized atoms to the fuel are analyzed. It is shown that an adequate description of condensation in a flame is impossible without consideration for the influence of electrophysical processes on nucleation and coagulation in the flame. It is established that ionization of the condensed phase is the most significant factor during coagulation of nano-oxide particles in a dust flame. This allows expecting that the influence on particle ionization may turn out to be an effective method of controlling the dispersion of the target products of gas-disperse synthesis.

This paper considers currently available models of irreversible deformation processes of materials under dynamic, in particular shock-wave, loading. The models can be divided into three groups: (1), macroscopic (continuum) models-traditional models of continuum mechanics, primarily classical models of elastic-plastic deformation, their various generalizations to the case of dynamic processes and models of viscoelastic relaxation media; (2) microstructural models based on the description of microstructural mechanisms of irreversible deformation (usually, the concept of the kinetics of a dislocation ensemble); (3) atomistic molecular dynamics models and calculations. A special category includes the most promising (from the point of view of the author) multilevel models which combine the advantages of each of these approaches and consider deformation mechanisms of various levels. Examples of calculations using such models are presented.