The principle of maximum pressure for subsonic stationary three-dimensional vortex flows of an ideal gas (author Sizykh G.B., 2018) is applied to verify the calculation method and its implementation on a specific computer technology. The four criteria for solution's verification are proposed. The method for obtaining flow parameters is based on solving of discrete analogs of the Navier --- Stokes system of equations on three-dimensional non-structured computational meshes. For example, there was consider the vortex tear-off flow around the fuselage of a helicopter with an empennage and landing gear at obviously insufficient computing resources. Conclusions of the feasibility of applying the author's criteria for evaluation of a particular calculation and for estimation of reliability of the results have been made.

: An experimental and theoretical study of the effect of polymer coatings on an epoxy-polyester base on the mechanical properties of samples in the form of steel plates has been carried out. It is shown that, despite the fact that the thickness of the coatings is only 100 μm, they have a significant effect on the mechanical properties of plates up to 1,5 mm thick, leading to a decrease in Young's modulus, tensile strength and ultimate deformations of the samples. It was shown that the elastic modulus of the coated plate cannot be determined unambiguously from tests for central tension and three-point bending. In bending tests, there is a more significant reduction in plate stiffness compared to tensile tests. This effect is confirmed by calculations within the framework of classical models of the theory of elasticity.

The most important step in the correct solution of discrete analogs of the equations of gas dynamics for the high-speed flow of a compressible chemically active gas using grid methods is to ensure sufficient grid resolution of regions with high gradients of gas-dynamic parameters, that is, the region of the departed curvilinear shock wave compressed and boundary layer. In this work, the grid independence of the main flow parameters on the dimensionality of the computational grid was checked on the problem of flowing a sphere by a high-speed flow of a gas mixture. The dependences of gas-dynamic flow parameters on the grid resolution along the normal to the sphere surface are revealed. The conclusions about the sufficiency of the grid resolution for a particular problem have been made.

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The authors showed the possibility of using mathematical models based on artificial neural networks to determine the aerodynamic characteristics of helicopter profiles, as well as the ability to design new pro-files with specified aerodynamic characteristics. At the first stage of work, an approximation model based on a neural network of the multilayer perceptron type was created to determine the coefficients of lift, drag, and pitch moment of the profiles. This topology has a number of distinctive features and is well suited for solving such problems. Neural network training was conducted. As a training set, the calculated data of 3692 aerodynamic profiles were used. The accuracy of the approximation of aerodynamic characteristics was estimated. The expediency of using artificial neural networks to solve this class of problems was substantiated. At the second stage of work, to obtain the geometry of new profiles, a mathematical model was created on the basis of special classes of artificial replicative neural networks, which allowed us to significantly reduce the dimension of the space used to describe the surface of the aerodynamic profile and create a qualitatively new design system. Examples were given of using the system for creating profile families in the region of specified aerodynamic characteristics and limiting the maximum relative thickness of the profile