Numerical simulation of the swirl generator discharge cone at lower runner speeds

The paper focuses on numerical analysis of hydrodynamic behavior in a discharge cone from a swirling flow generator when is operated at lower runner speeds. The swirl generator is used in laboratory instead of a turbine model in order to investigate different swirling flow configurations into a straight draft tube. The purpose for reducing the speed of the runner is to increase the investigation regimes. Numerical results have shown that reducing the speed of the runner from the swirl generator, we are able to obtain different flow configurations similar with a turbine model operated in a wide range of operating regimes.