Investigation of Several Turbulence Models in Simulation of an Axial PAT for a Small Hydropower Using as Renewable Source of Energy
Small hydropower stations as one of the clean and renewable resources of energy have great capacity to generate electricity and with increasing energy demands, using such potentials is quite necessary. One of the suitable choices for utilizing small hydropower resources is using pump as turbine (PAT), which means using pump in reverse mode. Pumps are relatively simple and inexpensive machines, easy to maintain and readily available in many of developing countries. Several methods have been developed to predict operation of pumps running as turbines but their results are not in good coincidence with experimental data for all pumps. Therefore, study and investigation of hydraulic behavior of pumps in reverse mode can be useful. In this work, an axial pump is simulated in reverse mode by computational fluid dynamics. Reynolds-Averaged Navier–Stokes equations are solved using different turbulence models in NUMECA software environment. Characteristic curves of the reverse pump are obtained for each turbulence model and results are compared with experimental data. The results show that Spallart-Allmaras can predict operation of the axial PAT better than other models.