Hydraulic Turbine Performance Assessment with Implementation of an Innovative Aeration System

Abstract

The environmentally friendly concept in terms of water quality represents a condition for developing hydropower plants all around the world. Since 2017, hydropower has represented more than 70% of all renewable energy production and it is essential for the integration of the other renewable sources of energy and for regulation of the grid. To maintain the “green” label concerning the dissolved oxygen level (6 mg DO/L), the energy suppliers should respond to environmental concerns about the operation of hydropower plants. In the context of sustainable development, the ecological degradation of rivers is unacceptable due to the implementation of a hydropower plant on the watercourse. For deep reservoirs or tropical regions, the oxygen level in the water downstream of the hydropower plants may be low and affect the aquatic life for many kilometers downstream. This paper presents a new aeration system for discharged water from hydropower plants that provides water aeration with minimum energy consumption. The influence of the aeration process on the turbine operation and efficiency is analyzed. Experimental measurements are carried out on site on a small Francis turbine. The influence of the aeration process on the turbine mechanical performances (vibration level and relative displacement) and hydraulic performances (turbine efficiency, power output, and pressure fluctuation) is analyzed. The results showed that the impact of the aeration device implementation and operation over the energetic characteristics of the turbine is in the efficiency measurements accuracy range. The aeration through this device did not influence the turbine operation (vibration, level, or pressure fluctuations).

An Overview of Active Control Techniques for Vortex Rope Mitigation in Hydraulic Turbines

“…Air bubbles had little or no interaction with the vortex core that had already been formed and did not converge in the central dead water zone. Bucur et al [39] and Bunea et al [40] proposed an innovative aeration device in a small Francis turbine (Figure 11). Although the main aim of their work was to develop an aeration device to increase the DO level for environmental reasons, the effect of air injection on the turbine s energy and vibration performance was also considered.…”

“…Due to the high cost of experimental tests and their inability to provide detailed information on internal flow characteristics, numerical simulations are often utilized to gain a better understanding of the flow mechanisms within turbines. However, research into application of air injection to suppress unsteady vortices in hydraulic turbines using Bucur et al [39] and Bunea et al [40] proposed an innovative aeration device in a small Francis turbine (Figure 11). Although the main aim of their work was to develop an aeration device to increase the DO level for environmental reasons, the effect of air injection on the turbine s energy and vibration performance was also considered.…”

Experimental Investigation of Centrifugal Pump Characteristics

“…Hydraulic machines are separated into two main classes as hydraulic turbines and pumps. While smaller hydraulic turbines are used to generate mechanical power using hydraulic lubricants in industries and vehicles, larger hydraulic turbines are often used in hydroelectric power plants to generate energy from the hydraulic power of water [1][2][3]. On the other hand, pumps are the tools that are used to move liquid fluids from one place to another in many areas like as cars, industry, construction sites, agriculture, and homes.…”