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The development of macroscopic inhomogeneities in in the form of Chernov-Luders bands and jump-like deformation bands (Portevin–Le Chatelier effect) in plastic metal flow is studied. For these two cases, regularities in the development of deformation inhomogeneity were established, and the kinetics of motion of the fronts of Chernoff–Luders bands and jump-like deformation bands was studied. It is shown that the Chernov–Luders fronts and the jump-like Portevin–Le Chatelier deformation can be considered, respectively, as macroscopic self-oscillatory processes of switching and excitation in deformable media of different nature.

The problem of the stress-strain state with axisymmetric steady-state deformation of thin-walled tubes is solved using the membrane theory of shells and the model of an ideal rigid-plastic material satisfying the Mises yield condition and the associated flow law. The obtained solution is used together with the empirical relation between the strain state at an arbitrary point of the free surface and the surface roughness parameters at the same point to determine the influence of some compression parameters of the tubes on the surface roughness parameters of the workpiece. The empirical relation is derived assuming that the free surface roughness parameters depend on two independent kinematic variables.

This paper describes a study on the possibility of increasing the efficiency of the resonance method of fracturing an ice cover due to the flexural-gravitational wave interference occurring in simultaneous movement of several air cushion vehicles.

An analytical solution of a plane stress problem for a cantilever beam made of a functionally graded material subjected to uniform loading is constructed. The material is assumed to be isotropic with constant Poisson's ratio and exponentially varying Young's modulus through the beam thickness. Expressions for displacements, strains, and stresses are obtained.

In this work, the stochastic wave finite element (SWFE) method for uncertain media through the second-order perturbation is formulated. A parametric approach for uncertainties is considered and combined to the finite element technique. The stochastic state space formulation is detailed in this work. The originality of this paper is the study of the second-order perturbation. The sensitivity and the precision of the SWFE approach are treated through the second-order perturbation introduced in the structural parameters. The question of the statistics of the propagation constants and the wave modes is considered. Comparisons with analytical results and Monte Carlo simulations are performed.

The energy balance of laser cutting of low-carbon and stainless steel sheets with the minimum roughness of the cut surface is experimentally studied. Experimental data obtained in wide ranges of cutting parameters are generalized with the use of dimensionless parameters (Peclet number and absorbed laser energy). It is discovered for the first time that the minimum roughness is ensured at a certain value of energy per unit volume of the melt (approximately 26 J/mm³), regardless of the gas type (oxygen or nitrogen) and laser type (fiber laser with a wavelength of 1.07 mm or СО₂ laser with a wavelength of 10.6 mm).

The equations of the longitudinal motion of flying vehicles at their steady and unsteady motion are considered. The nondimensionalization of equations has been carried out, and the similarity criteria have been obtained. The capabilities of the experimental modeling of the unsteady motion of flying vehicles are illustrated with the aid of small-scale models.

Nonequilibrium flows of a two-component oxygen mixture O₂/O behind a shock wave are studied with due allowance for the state-to-state vibrational and chemical kinetics. The system of gas-dynamic equations is supplemented with kinetic equations includ-ing contributions of VT (TV)-exchange and dissociation processes. A method of the numerical solution of this system with the use of the ANSYS Fluent commercial soft-ware package is proposed, which is used in a combination with the authors’ code that takes into account nonequilibrium kinetics. The computed results are compared with parameters obtained by solving the problem in the shock-fitting formulation. The vibrational temperature is compared with experimental data. The numerical tool pro-posed in the present paper is applied to study the flow around a cylinder.

The paper presents hyperbolic models for dusty gas flow formulated for single- and multivelocity approximations with account for inter-fractional heat transfer. Characte-ristic analysis of equations for the model was performed. The Godunov method and linearized Riemann solver was applied for a solution on curvilinear mesh: the Prandtl–Meyer problem for air-droplet mixture was solved. The simulation results were compared with the self-similar solution.

A numerical study of the aerodynamics of a building of a complex shape has been performed taking into account the location of surrounding buildings. Simulation data based on full mathematical models of continuum mechanics have allowed us to reveal the spatial structure of the turbulent separated atmospheric flow in the neigh-borhood of the building, and to evaluate the wind load exerted on the building. A comparison between the calculated data for the air flow past the examined building located in a group of other buildings and past the same building at its isolated location was performed. Based on the obtained data, the impact of interference effects on the aerodynamics of buildings in urban areas was evaluated. A comparison of calculated with experimental data was performed. A satisfactory agreement between the two datasets was obtained.