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This paper presents the results of experimental studies and numerical simulation of heat and mass transfer in a high-viscosity hydrocarbon liquid with temperature dependent viscosity and thermal conductivity, under the influence of a high-frequency electromagnetic field with natural thermal convection taken into acount.

Propagation of electromagnetic radiation in a moving three-layer medium is studied. It is shown that travelling temperature waves are formed due to interference of the incident wave with the wave reflected from the interface between the layers with radiation energy dissipation. The frequency, length, and velocity of these waves are found to depend on the electromagnetic radiation frequency, electrophysical and thermophysical parameters of the medium, and velocity of medium motion.

The effect of a strong shock wave on a weakly ionized collisional plasma was studied. The structure of the ion-acoustic perturbation caused by the shock wave was numerically investigated. The effect of the nonlinearity, dispersion, and dissipation on the formation of an oscillating wave profile was shown. It is found that in some modes, an increase in the shock wave velocity leads to a sharp increase in the concentration of charged particles and a reduction in the number of perturbation maxima. This change of the flow structure can be preceded by the formation of localized regions with an increased degree of plasma ionization. It is shown that the presence of plasmoids can lead to a strong influence of charges on the neutral component.

This paper considers wave processes in a centrifuged layer of an incompressible viscous conducting fluid in an axial magnetic field in the cavity of a rapidly rotating infinite cylinder with insulating walls. Inertial modes-solutions of the linearized boundary-value problem of magnetohydrodynamics - are represented as a superposition of helical fields. Expressions for the vorticity parameters of the helical flows forming the inertial mode at a small Stewart number are given. Dispersion curves of inertial waves are constructed, and the influence of the magnetic field on the flow field is analyzed. The critical frequencies at which the lowest (surface) mode arises are determined. The spatial and temporal stability of the modes are investigated.

Results of experiments on loading a pack of closely packed metal plates by an oblique shock wave are reported. Buckling of the interface between the plate is observed. It is shown that periodic wavy perturbations are formed due to the development of the Kelvin-Helmholtz instability within the time of interface turning induced by the shock wave action. The final amplitude and wavelength of perturbations are found to be determined by the thickness of the weakened layer in a plastic flow.

This paper presents an analysis of the accuracy of known and new modeling methods using the hypothesis of local and plane sections for solution of problems of the impact and plane-parallel motion of conical bodies at an angle to the free surface of the half-space occupied by elastoplastic soil. The parameters of the local interaction model that is quadratic in velocity are determined by solving the one-dimensional problem of the expansion of a spherical cavity. Axisymmetric problems for each of the meridional section are solved simultaneously neglecting mass and momentum transfer in the circumferential direction and using an approach based on the hypothesis of plane sections. The dynamic and kinematic parameters of oblique penetration obtained using modified models are compared with the results of computer simulation in a three-dimensional formulation. The results obtained with regard to the contact stress distribution along the generator of the pointed cone are in satisfactory agreement.

Dispersion characteristics of wave processes in collapsible elastic biovessels with the biofluid flowing through them are presented. The possibility of the existence of fixed flow structures in the vessels is shown. The possibility of applying the results to the study of biological systems is considered.

Results of studying impingement of a supersonic underexpanded air jet onto a finite-thickness porous metal obstacle whose frontal plane is normal to the jet axis and whose side surface is impermeable for the gas flow are reported. The case of a non-porous obstacle of the same diameter is considered for determining the effect of porosity on gas-dynamic characteristics of jet-obstacle interaction.

A mathematical model of the flow in a round submerged turbulent jet is considered. The model includes differential transport equations for the normal components of the Reynolds stress tensor and Rodi's algebraic approximations for shear stresses. A theoretical-group analysis of the examined model is performed, and a reduced self-similar system of ordinary differential equations is derived and solved numerically. It is shown that the calculated results agree with available experimental data.

A new algorithm (NWTA-algorithm) for solving the traveling salesman problem (TSP) is proposed. The algorithm is based on the use of the Hopfield recurrent neural network, the WTA method (“Winner takes all”) for the cycle formation, and 2-opt optimization method. A special feature of the algorithm proposed is in the use of the method of partial (prefix) sums to accelerate the solution of the system of the Hopfield network equations. For attaining additional acceleration, the parallelization of the algorithm proposed is performed on GPU with the CUDA technology. Several examples from the TSPLIB library with the number of cities from 51 to 2,392 show that the algorithm proposed finds approximate solutions of the TSP (a relative increase in the length of the route with respect to the optimum is 0.03 ÷ 0.14). With a large number of cities (130 and more) the NWTA-algorithm running duration on the CPU is in 4 ÷ 24 times less than the duration of the heuristic LKH algorithm giving optimal solutions for all TSPLIB examples.