Numerical and Experimental Evaluation of Concave and Convex Designs for Gravitational Water Vortex Turbine

Abstract

The small hydroelectric power plants have become a great solution to the energy problem in the non-interconnected zones that have a low flow river. The gravitational vortex turbine is a small power plant easy to install, low maintenance and economically viable for these areas. However, the turbine has a low efficiency. Although changes in geometry could increase it. In this study, concave and convex designs are proposed for the gravitational vortex turbine tank which are studied numerically and experimentally. The numerical study was developed in ANSYS CFX V19.1 software and the experimental phase was carried out in the fluid’s laboratory of the Instituto Tecnológico Metropolitano. The numerical and experimental results of the concave and convex design show a difference of 62% and 60%, respectively. The vortex formation and output velocity are the numerical parameters analysed with the software, and the electric power and torque are the parameters on the experimental phase. The tank geometry is the most important parameter to increase the turbine’s efficiency, so it is recommendable to select a suitable design.