Effect of Hydrodynamically Designed Blades on the Efficiency of a Michell-Banki Turbine

This work presents a numerical study conducted in ANSYS CFX® V18.1 that seeks to improve the efficiency of a Michell Banki turbine by modifying one of its geometric parameters: the profile of the blades in the runner. Four aerodynamic profiles, 20-32C, A18, NACA 9412-15 and NACA 9412-ST, were selected and modified. Subsequently, they were integrated into the turbine runner to compare their performance to that of a turbine model configured with the conventional blade profile by means of computer simulations. In total, five (5) turbine models were studied under the same operating conditions: inlet flow velocity, 3.6 m/s; runner angular velocity, 450 RPM; and outlet pressure, 1 ATM. The simulation results revealed an efficiency increase of 7.37%, 7% and 0.76% with 20-32C, NACA 9412-ST and NACA 9412-15 blade profiles, respectively.