Efect of Different Configurations on 3-D Analysis of Flow Through Stay Vanes and Guide Vanes of a Francis Turbine

Stay and guide vanes (distributor) are essential parts of a turbine. They are used to control the ow rate and to appropriately transfer the ow momentum to the runner. In this work, ow through the distributor is analyzed. For various Boundary Conditions (BC) and di erent con gurations, threedimensional ows in the distributor of a Francis turbine are evaluated and compared with each other. The numerical simulations were carried out using Fluent software and the results were validated with a GAMM Francis turbine, where the geometry and detailed best eciency measurements were publically available. In these simulations, the ow was assumed to be steady and the e ect of turbulence was included using the k 􀀀 «turbulence model. The study showed that an accurate prediction of velocity and pressure elds through the distributor may be obtained by considering a representative runner chamber with a single passage, including one blade of a stay and guide vane con guration. Furthermore, the corresponding needed computational resources for such an analysis are quite modest.