The investigation of aerodynamics and the establishment of flow patterns around finite-length cylinders with various end shapes in a free, boundless air flow with longitudinal and transverse flow over a wide range of geometric and regime parameters is sketchy and does not have a wide range of geometric and regime parameters. This, in turn, affects the entire aerodynamics of the streamlined body. This paper considers the numerical simulation of a wind turbine made of combined blades. CFD (computational fluid dynamics) methods based on the realisable k-ε turbulence model were used in the study. The results on the influence of the position of the fixed blade on the angle of inclination are obtained (0°, 15°, 30°, 45°, and 60°). The authors found that the pressure of a fixed blade at an optimal angle increases the power coefficient Cp by 35–40%. The dependence of the Cp power coefficient on the rotational speed (speed coefficient) for a three-bladed wind turbine was also established, and it was determined that the maximum value of Cp = 0.28 at Z = 4.9. Based on the results obtained, it was determined that the wind turbine has a maximum power coefficient at an angle of inclination of 0 degrees.

Numerical and experimental methods are used to investigate the aerodynamic characteristics of a laboratory model in the form of a cylinder with an active rotating element (deflector) that can be used as a working blade of a wind turbine. Numerical simulation was based on solving the Reynolds-averaged Navier–Stokes equations for the realizable (\(k{-}\varepsilon\)) turbulence model using the Ansys Fluent software. Experimental studies were performed using a laboratory model with a cylinder 205 mm long and 50 mm in diameter and a deflector 100 mm in diameter, which was produced based on the results of the numerical simulation. A comparative analysis of the numerical and experimental aerodynamic characteristics of the model was carried out and the aerodynamic features of the airflow around the test model were identified.

Wind energy is a commercially proven and rapidly developing type of electricity generation. Wind power plants with a vertical axis are more attractive and better suited for use in cities and urban environments where wind flow is less predictable compared to widespread wind power plants with a horizontal axis of rotation. This makes them a much better choice for both ground installation and/or for mounting on buildings and roofs that would otherwise limit the installation of higher horizontal turbine structures. The paper describes an experimental study of the drag force and its coefficient for wind turbines with a vertical axis of rotation. The object of the study is a laboratory model of a wind turbine with blades made in the form of rotating cylinders with a fixed blade. Experimental studies were carried out in the T-1-M wind tunnel, measurements of aerodynamic force were carried out using three-component scales. A distinctive feature of the work is the combined use of the lifting force of the cylinders, as well as the lifting force of the fixed plate. Due to this solution, when comparing with existing wind turbines with a vertical axis of rotation, it was found that the wind turbine in question prevails by 25‒100 % in the number of revolutions. The dependences of the drag force on the flow velocity and the drag coefficient on the Reynolds number from 1·10⁴ to 4·10⁴ are obtained. An uncertainty analysis was also carried out in order to determine the uncertainty by type A, B and the total uncertainty, from which it was found that the measurement error was 1.13 %. The field of the practical application of the results obtained in laboratory studies will be useful in the development of prototypes of wind turbines with a vertical axis of rotation

The efficiency of electricity generation by solar panels depends on many factors, one of which is the temperature of the semiconductor layer. An increase in this parameter leads to a decrease in the efficiency of the module, since the speed of electron movement increases, therefore, the resistance increases. Conversely, the lower the temperature of the silicon cells, the lower the resistance and the higher the efficiency. However, the temperature of the silicon cells depends on a number of parameters: wind speeds, insolation, and ambient temperatures. Therefore, depending on the region and time of year, the same solar module will have different performance. Based on this, an urgent issue when planning the use of solar panels is the possibility of determining how much the efficiency of photovoltaic conversion in a particular area will decrease. Therefore, to study the variability of efficiency indicators, a simulation of the temperature change of the semiconductor layer of the polycrystalline solar panel KZPV 220 M60 was carried out, taking into account climatic parameters in winter and summer days for three cities of Kazakhstan — Petropavlovsk, Karaganda and Shymkent. As a result of modeling, it was found that on July 12, solar cells reach their maximum temperature of 64.4 °C in Shymkent, 49.8 °C in Karaganda and 52.1 °C in Petropavlovsk, while efficiency decreases by 2.7 %, 1.7 % and 1.8 %, respectively, relative to the efficiency of the solar module under standard conditions (insolation 1000 W/m2, temperature 25 °C, spectrum AM = 1.5). At the same time, on December 12, Tmax: in Shymkent 11.5 °C, in Karaganda — 15.8 °C, in Petropavlovsk — 16.7 °C, and efficiency increases by 0.9 %, 2.7 %, 2.8 %, respectively.