Numerical Investigation in the Vaned Distributor under Different Guide Vanes Openings of a Pump Turbine in Pump Mode

The performance of a pump turbine in pump mode is of great importance to a pumped storage power plant. In order to obtain pump characteristics of a pump turbine, 3D steady simulations were carried out by solving Reynolds-averaged Navier-Stokes (RANS) equations using different two-equation turbulence models. Compared with the experimental data, SST k-epsilon turbulence model was chosen to simulate external characteristic curves under 32mm, 22mm and 18mm guide vanes openings. The results show a good agreement with the experimental data, especially near the best efficiency point. Finally, the detailed analysis was conducted within vaned distributor for these three guide vanes openings. The variation of flow field, pressure filed, energy characteristic and loss with the discharge and guide vanes opening were obtained through the analysis. This research could provide a basic understanding on pump characteristics of a pump turbine for designer.