motion of the body are obtained, which can only be solved numerically. The equilibrium equations are solved and the basic stationary modes of body motion are obtained. The main result is the most gentle body planning mode. In the matlab computer mathematics system, a set of programs is written that searches for a numerical solution and outputs trajectories. The movement of the modes under consideration is modeled and the stability of the main modes is looked at using numerical calculations.

Keywords: body, planning mode, stability, geometric dimensions

The paper considers a mathematical model of a Darye wind turbine with three blades. The operating mode of the fast rotation of the wind turbine has been obtained. It is called autorotation mode. An assessment of the speed of the wind turbine in this mode was obtained, an assessment of the power and geometric dimensions of the structure under consideration was carried out. Programs have been written in the matlab system and numerical calculation results have been obtained. The efficiency of Darye wind turbines with a different number of blades is compared and it is shown that in practice it is best to use three blades.

Keywords: body, planning mode, stability, geometric dimensions

In the article, a mathematical model of the oscillations of an aerodynamic pendulum in the flow of a moving medium is constructed and investigated. As a model of the effect of the medium on the body, the model of quasi-static flow around the plate by the medium is adopted. According to this hypothesis, the aerodynamic forces acting on the body are applied at the center of pressure. In our problem, the pressure center is movable relative to the plate. The equations of motion for the body under consideration are obtained. The transition to new dimensionless variables has been carried out. The violation of uniqueness in determining the angle of attack at points where the air velocity of the pressure center is close to zero is shown. Envelopes for some areas of ambiguity are constructed using multiple solutions of algebraic nonlinear equations derived from kinematic relations. To do this, the coordinates of the return points are determined, the solution of the equations themselves is found, and the boundaries of the areas of ambiguity are depicted. In the mathematical package MATLAB 18, a program is written that.

Keywords: body, ambiguity area, envelopes, return points

In this paper, a mathematical model of a wind generator similar to the Darya rotor has been developed. The fast turbine rotation mode or autorotation mode is considered. Using the averaging method, the value of the steady-state angular velocity of the wind turbine in the autorotation mode is obtained. A set of programs has been written in the matlab computer system and numerical counting results have been obtained. They are compared with analytical estimates. A parametric analysis of the geometric dimensions of the wind turbine was carried out to obtain a given power. The advantages and disadvantages of this design in comparison with other types of wind turbines are shown. As a result of these calculations, it can be concluded that Darye wind turbines will be effective only for obtaining small power and at small sizes. Large devices fail too often and their maintenance is too expensive.Large devices require too expensive maintenance.

Keywords: wind turbine, autorotation mode, stability, geometric dimensions

This work investigated the influence of the type of vertical switching on the level of thermomechanical stresses and temperature deformation in a three-dimensional microassembly. Three microassembly models with the most common types of vertical connections were considered: solder balls in the package holes, metallized holes in the package, and end-switching tracks. For each of the three models, the effect of the sealing compound parameters on the thermomechanical load was additionally investigated.

Keywords: microassembly, packaging, electronic component base, three-dimensional integration, vertical switching, thermomechanical stress, thermomechanical deformation, thermal coefficient of linear expansion, thermomechanical modeling