Pressure measurements and high speed visualizations of the cavitation phenomena at deep part load condition in a Francis turbine

• Published in: IOP conference series. Earth and environmental science Vol. 22; no. 2; pp. 22011 - 22018
• Main Authors: Yamamoto, K, Müller, A, Favrel, A, Landry, C, Avellan, F
• Format: Journal Article
• Language: English
• Published: Bristol IOP Publishing 01.01.2014
• Subjects: Cavitation; Draft tubes; Electric power generation; Fluid dynamics; Fluid flow; Full load; High speed; Hydraulic equipment; Hydraulic loading; Hydraulic turbines; Hydraulics; Outlets; Power plants; Turbines
• ISSN: 1755-1307; 1755-1315
• DOI: 10.1088/1755-1315/22/2/022011

In a hydraulic power plant, it is essential to provide a reliable, sustainable and flexible energy supply. In recent years, in order to cover the variations of the renewable electricity production, hydraulic power plants are demanded to operate with more extended operating range. Under these off-design conditions, a hydraulic turbine is subject to cavitating swirl flow at the runner outlet. It is well-known that the helically/symmetrically shaped cavitation develops at the runner outlet in part load/full load condition, and it gives severe damage to the hydraulic systems under certain conditions. Although there have been many studies about partial and full load conditions, contributions reporting the deep part load condition are limited, and the cavitation behaviour at this condition is not yet understood. This study aims to unveil the cavitation phenomena at deep part load condition by high speed visualizations focusing on the draft tube cone as well as the runner blade channel, and pressure fluctuations associated with the phenomena were also investigated.