Effective Basin–Blade Configurations of a Gravitational Water Vortex Turbine for Microhydropower Generation

Abstract

Among various microhydropower plants, gravitational water vortex power plants are emerging because of their simple installation, reduced setup time, and minimal maintenance cost. The methodology and the selection of a suitable basin and turbine blade combinations are yet to be explained by researchers. This study attempts to investigate the parameters that affect the formation and strength of a vortex for efficient power generation using an artificially induced air-core vortex. Computational fluid dynamics based on a two-phase flow analysis of the vortex formation at different basin parameters resulted in the selection of a suitable configuration of the basin. The basin was then used in the blade analysis with different blade shapes at various load conditions. An experimental setup was also fabricated for the validation of the numerical results, in which a close agreement was observed. The proposed methodology could be used to determine the plant specifications and the blade size and shape for various flow rates and heads. The role of vortex height in determining the performance of the gravitational water vortex turbine was explored. Among the four types of blades used in the study, cross-flow blades have shown the best efficiency for the same discharge and head conditions.