КОМПЛЕКСНА ОЦІНКА ОБҐРУНТУВАННЯ ВИБОРУ ТИПУ ВИСОКОНАПІРНОЇ ГІДРОТУРБІНИ

Hydraulic turbines are used to convert the energy of flowing water into rotational mechanical energy. Hydraulic turbines are operated under different conditions, so changes in power consumption and inlet flow conditions must be taken into account. In high specific speed hydroturbines, part load operation and cavitation conditions create very complex internal flow structures that are difficult to predict accurately while maintaining reasonable computational costs. Cavitation is a problem in hydroelectric power plants and is more noticeable in hydroturbines operating outside of design conditions. Pelton turbine, a hydraulic prime mover, uses the kinetic energy of high-pressure water jets to rotate the rotor blades, converting water energy into mechanical energy. Due to its simple design and the possibility of use in high and ultra-high pressure conditions, it has been the main equipment of power plants for many years. Francis turbine are widely used throughout the world due to their adaptability, high efficiency and versatility in a wide range of operating conditions. Taking into account the significant overlap of the working ranges of Francis and Pelton turbines (200–800 m), for specific projects, a comprehensive assessment of the justification for the choice of the type of high-head hydraulic turbines is required. Designing a high-head Francis and Pelton turbines is difficult due to the complex flow pattern in the flow space elements. Sediment erosion has a significant impact on hydraulic mechanisms, especially Francis turbines, when operating in sediment-laden streams. This phenomenon plays a crucial role in reducing power generation and operational problems. Considering that Francis turbines play a vital role in hydropower generation and are the most widely used hydroturbines, they must withstand significant sediment erosion. This article describes the relative advantages of each type of aggregate for different conditions and operating modes. In addition to hydraulic parameters, economic justification and durability of work, it is necessary to take into account the sensitivity of hydraulic turbines to sand erosion. The article provides an overview of the types of high-head hydraulic turbines and the justification for their choice in the design of high-head hydroelectric power plants. Comparison of active and reactive hydraulic turbines was made. Issues related to designing of elements of flow space of hydraulic turbine are considered.