• Energy Research

The object of research is the shape of the blade of a vertical-axis installation. The problem solved in this work is to find the optimal shape of the blade for a wind power installation for operation at low wind speeds or in areas where its flow is limited. In the course of the work, the interaction between each blade option and the wind flow depending on the shape of the blade was considered. With the help of a reduced model of the wind turbine, a flat blade, a blade with a «pocket», and a blade with a «pocket» and a slit were tested. The test results prove the effectiveness of the designed and manufactured blade with a «pocket» and a slit. This was confirmed by the study results, according to which, during the experiment, the number of revolutions of a wind turbine with blades made with a «pocket» and a slit was the largest. In comparison with flat-shaped blades, the increase was 20 %, and, in comparison with blades with a «pocket», the increase was 10 %. In order to compare wind turbines that have flat-shaped blades and blades with a «pocket» and a slit, experimental studies and calculations of the power factor Ср were carried out. A flat-blade wind wheel has Ср1=24; a blade with a «pocket» – Ср2=52.9; a blade that has a «pocket» and a slit – Cp3=58.7. Therefore, one can assume that the power generated by the wind wheel with the above blades is also the largest, Р3=98 W, compared to two other shapes of blades: flat, P1=32.3 W; with a «pocket», Р2=88.2 W. It would increase during the test time from zero speed to reaching a constant rotational speed. The studies confirm that the wind wheel, which has blades with a «pocket» and a slit, has the highest speed of rotation over the entire period of time when measurements were performed

The reliability of pumping units at nuclear power plants (NPPs) is critical in terms of their energy efficiency and safety. Remarkably, WWER-1000 reactors at Ukrainian NPPs are equipped with outdated pumping units that have already served their full-service life. This fact leads to an urgent need to develop a new, more efficient pump. In the article, a promising pump, ACNA 600-35, was developed. It was designed to increase the energy efficiency of pumps TX 800/70/8-K-2E, applied at the holding pool and the industrial circuit of the nuclear reactor. Since these pumps should be imported from the monopoly suppliers, this affects both the energy efficiency of pumping equipment and the energy independence of Eastern Europe. The proposed pump ACNA 600-35 is characterized by an increased efficiency of up to 0.12–0.13 compared with the TX 800/70/8-K-2E pump. In general, the life cycle cost of the proposed pump is 15–20% lower than for the analog TX 800/70/8-K-2E. The design of the developed pump ACNA 600-35 and the related pumping unit based on its production at industrial facilities allows for further development of the industrial and fuel-energy complex, increasing the state’s energy independence and employment. According to expert estimates, the average economic effect from supplying the developed pump can reach 10 mln USD/year.

The rational choice of pumping units and the effective usage of the corresponding pumping equipment are urgent problems in terms of ensuring the energy efficiency of up-to-date enterprises. The research aims to develop an energy efficiency indicator for torque flow pump usage to improve the decision-making procedure for choosing the corresponding pumping equipment for specific production conditions. Based on a study of the requirements of international standards for energy efficiency, a methodology for evaluating torque flow pumps according to the energy efficiency indicators is proposed, as the ratio between the values of the average compensated network power and the reference pump inlet power can determine the degree of reduced energy equipment operation efficiency in terms of the energy efficiency of pumping liquids. It was proposed to apply the base point method to determine the so-called compromise point of energy consumption for liquid pumping. This is a point for which another point, by the Pareto compromise, is likely to have a more significant (worse) value for energy consumption than the rest of the set of possible values.

The article is devoted to studying the contra-rotating stages with different impellers and blade discs. Determining the reduction of volumetric losses by modeling the contra-rotating stages in the software package ANSYS CFX. The work aimed to create and study the flow and characteristics: semi-open, closed impellers, and blade discs. As a result of the work, the following contra-rotating stages were determined and compared: the semi-opened impeller with the semi-opened blade disc; the closed impeller with the closed blade disc; the semi-opened impeller with the closed blade disc; the closed impeller with the semi-opened blade disc. As a result of research, fluid flows in contra-rotating stages and their characteristics in the form of pressure and efficiency were obtained. According to the obtained data, the expediency of using contra-rotating stages as a working body of the pump is written.