| dc.description.abstract | A free vortex is a region in which the flow rotates around an axis line without any external force. In gravitational water vortex turbines, water passes through an open inlet channel and enters the basin tangentially to form a powerful eddies. Then, the tangential rotating force of the water is transmitted to the turbine. This study presents the results of a study on the effect of the number of turbine blades on the efficiency of a gravitational water vortex turbine. The analysis was performed using simulations on ANSYS Fluent, and experimental method settings were made to validate the simulation results. Variations in the number of blades used are 5 blades, 7 blades and 9 blades and tested to see the effect of variations in the number of blades on turbine performance, and the results show that the 9 blade turbine produces the highest torque and efficiency in receiving energy from the flow of water. The simulation results of CFd on 5 blades, 7 blades, and 9 blades turbines produce torque of 13.44 N.m, 14.6 N.m and 21.89 N.m, respectively. The results of experimental testing on 5 blade, 7 blade, and 9 blade turbines respectively produce torque of 12.75 N.m, 15.69 N.m and 17.65 N.m and produce efficiency in each number of blades of 41.9%, 43, 5% and 45.1%. The results showed that the more blades used, the greater the energy from the water that could be absorbed, so that the torque and efficiency would increase. | en_US |
