STUDY OF THE EFFECT OF THE FAST FRANCIS TURBINE BLADES’ SPIN AROUND AN AXIS, FOLLOWING CFD ANALYSIS OF FLOW AND RESULTS OF MEASUREMENTS IN THE LAB
The present paper propose an analysis of the rotation around an axis effect of the runner blades that compound the fast Francis turbines in order to increase their energo-cavitational performances. First step was done after the analysis of the runner which resulted from the calculations and hydro-dynamic design. This analysis was performed both theoretically using the finite element software package called CFX Blade Gen, and through experiment within the Test Laboratory for Hydraulic Turbines from Hydro-Engineering. Second step of the research consisted in rotating the blade around the axis with a certain angle in order to increase the absorbed flow, holding the rim and the ring from the initial blade. Rotating was performed in different angles by making the finite element analysis for all the rotating angles. In order to improve the cavitational component it was proposed and realized an extension of the blade with an appropriate covering degree, without any visible effect over the energetic features, these being maintained within the permitted error range that admitted by the IEC 60193 code.
Keywords: blade, runner, Francis
Cuvinte cheie: paleta, rotor, Francis