Hydrodynamic Characterization Of Small-Size Kaplan Turbine

This paper reports the results of simulating the steady and cavitating flows through a low-head small-size Kaplan turbine. The computed hydraulic performance depicts a moderate efficiency of this Kaplan turbine owing to the high specific speed and the large gap between blades and shroud. The effects of blade setting angle, vane opening, discharge, and rotational speed on the hydraulic performance are discussed. The formation of cavities in the runner blades occurs at certain operating conditions and the cavities typically appear over the fore of blade suction side and the blade tip. In addition, the criteria of cavitation inception are revealed. These results provide useful information how to improve the design of this category of Kaplan turbines. (c) 2020 American Society of Civil Engineers.