Enhancement on Self-Starting Darrieus Bladed Wind Turbine Using J-Shape Airfoil

Abstract

Conventional Darrieus wind turbine faces a challenge to self-start in low wind speeds but their performance during operation is better than that of Savonius wind turbines which means that there is room for improvement for Darrieus wind turbine. In this paper, study has been focused to design and develop a modified-Darrieus wind turbine blade based on J-NACA0010, J-NACA0015 and J-NACA0018 airfoil profile. Performance study will be assessed in terms of its self-starting capability, tip speed ratio, angular speed and power output of the proposed system for all the above-mentioned modified airfoils. The J-shaped blade has a higher overall performance compared to the others because unlike the conventional Darrieus wind turbines which depends mostly on lift forces. The modification to the blades in cooperates drag forces is projected can produce better starting torque which solves the problem of self-starting in the conventional Darrieus wind turbines. From the experimental findings, it has been found that J-NACA0018 has recorded to achieve the largest power coefficient among the other airfoils with 0.558 as its (Cp) and generated power of approximately 40 mW, which is the highest among the rest. The J-NACA0018 also has the fastest recorded time for self-starting with 1.45 seconds.  This is due to fact that the airfoil has a larger surface area in the blade which contributes to a larger drag force and thus contributed to the power generation and power coefficient. The highest torque coefficient was produced by J-NACA0015 at 0.714.