Performance Study of Cross Flow Hybrid Hydrokinetic Turbine

Abstract

Hydrokinetic turbine is considered to be promising for extraction of flow energy in gravity-powered open channels. There are various types of hydrokinetic turbines (Savonius type and Darrieus type) being developed and tested under various researches. Their performance results are available in the literature. The hybrid rotor is a combination of Darrieus and Savonius rotor which can have useful characteristics of both the rotors. A detailed numerical analysis of such system has been carried out and presented in this paper. NACA0018 symmetrical hydrofoil is selected for the development of profile of Darrieus rotor. The study aims to investigate the aerodynamics and performance analysis of hybrid hydrokinetic turbine. In order to enhance the starting characteristics, a 3D model of hybrid rotor along with channel is prepared, and realizable k-e turbulence model has been employed to perform CFD analysis. Based on the results, it has been found that the hybrid hydrokinetic rotor has better aerodynamics behavior than single Savonius and Darrieus rotor. The performance is found to be better than Savonius rotor. Under future studies, the findings of the study may be useful for developing prototype of such a system for field study.