Numerical study on the performance and flow field of varied conical basin for efficient gravitational water vortex power plant

Abstract

Nowadays, utilization of hydropower is still focussed on the development of large dams which have an effect on the natural environment and are often opposed by the people in the region. Producing electricity from small water resources, especially using the gravitational vortex method has currently attracted the interest of researchers. In this paper, a numerical study of the effect of vortex pool variation on the performance and flow field of gravitational water vortex power plant (GWVPP) are investigated. Numerical study based on the volume of fluid (VOF) method is developed in ANSYS FLUENT code program for analyzing the parametric studies of GWVPP. Cylindrical vortex pool coupled with gravitation type water turbine based on Nishi and Inagaki (2017) research, are modified become conical vortex pool type by varying the ratio of inlet diameter and outlet diameter (Din/Dout) by 3.26; 4.9; and 6.12. Turbulent model is approached using RNG k-epsilon and boundary conditions are set 2.838 kg/s for inlet mass flow rate, 0 Pa for open and outlet boundary. As a beginning result, the computational values of this study and experimental data of the torque and turbine output from Nishi and Inagaki (2017) agreed with one another. Later, for conical basin with variation of Din/Dout, it can be shown that the maximum velocity profile achieved in nearly to the discharge hole, in order from 6.12; 4.9; followed by 3.26 of the Din/Dout ratio respectively. It is supported by the increase in the Din/Dout ratio or decrease output hole, the air area increase and creat greater vortex circulation.