11th European Conference on Turbomachinery Fluid dynamics & Thermodynamics
Self-rectifying turbines, providing unidirectional rotation for an alternating airflow, is an interesting impulse turbine for OWC plants. Despite of being penalized by its low maximum efficiency with respect to Wells turbines, it presents notable advantages that need to be explored with more knowledge of the flow pattern. For that purpose, a new set of simulations has been performed from a model previously developed and validated. The aim is to analyze the unsteady features of the flow and the rotor-stators interaction using a deterministic analysis. The simulations were developed in ANSYS FLUENT v12 and the results are presented in terms of turbulent kinetic energy and deterministic stresses. It is concluded that inner vanes (IV) of the turbine are identified as a critical contributor of generation of turbulence and unsteadiness in both outward and inward radial flows. Redesign of the IVs row is revealed necessary to improve the performance of the self-rectifying turbine.