MODERNIZATION OF THE RUNNER BLADE SYSTEM OF A HIGH-HEAD FRANSIC TURBINES

Hydropower plays an essential role in the energy sector. Efficient use of hydropower plants can significantly save fuel and energy resources. Hydroelectric power plants provide electricity generation, grid frequency and capacity regulation, peak load coverage, and emergency reserve. Developing and implementing the latest technologies in this area contribute to efficiently using water energy resources. A significant advantage of hydropower is the renewability of the energy source. Ukraine has considerable water resources potential for the development of the hydropower industry. The hydroturbines developed and supplied to the market must ensure high technical and economic performance, reliability, and durability,guaranteeing high competitiveness of hydroturbines in the foreign and domestic markets. Numerical and physical modeling methods are widely used to solve these problems. The development of mathematical modeling methods makes it possible to conduct multidimensional numerical studies of the influence of geometric parameters on the formation of energy characteristics in designing elements of the flow space of a hydraulic turbine. Modern modeling and analysis technologies provide an opportunity for a detailed study of the impact of changes in the flow space design elements on theenergy characteristics of hydraulic turbines. The central component of Francis turbines is the runner with a blade system, on which the installation's productivity, reliability, and durability depend. Changing the shape and location of the impeller blades can lead to a decrease in energy losses, an increase in efficiency, and a reduction in cavitation. In many cases, a numerical experiment is an adequate replacement for a physical one. The results of numerical and physical experiments on the influence of geometric parameters on energy characteristics are widely used in the generally accepted approach to improving the flow space of a hydroturbine, which is based on making changes to the geometry and further evaluating these changes. The paper considers improving the energy-cavitation characteristics of the blade system of a turbine Francis by modernizing its geometric parameters.