Performance analysis of micro-class Francis hydro turbine by CFD

Abstract

Hydropower is the largest source of renewable energy. Francis hydro turbines are the world's most widely used hydro turbine. In this paper, CFD software used to simulate for the performance analysis of micro-class Francis hydro turbine. A draft tube is one of the most important parts of Francis turbine which connects the runner exit to the tailrace where the water is being finally discharged at atmospheric pressure from the reaction turbine. There are several issues in the draft tube like a pressure pulsation, effect of cavitation of draft tube performance, vortex rope study etc. At part-load condition vortex form, it hits structure constantly which affect the performance of the turbine. This study focused on prediction of vortex behavior at the draft tube and numerical results obtained the hydraulic performance of 3KW micro Francis turbine with the inlet pipe, a spiral casing with 12 guide vanes, 6 stay vanes and the runner 13 blades and a draft tube. Additionally, results from the CFD simulation and experimental results will be compared to 3KW micro-Francis turbine with misaligned guide vane.