Abstract
In order to improve the aerodynamic characteristics of the Straight-bladed Vertical Axis Wind Turbine (SB-VAWT), a rotor structure with auxiliary blade installed behind the main blade was proposed in this study. To investigate the effects of relative thickness and the fixing angle of the auxiliary blade on aerodynamic characteristics of SB-VAWT, numerical simulations were carried out. Two shapes of NACA 4-digital series blade-section, NACA0018 and NACA0024, were selected as the main blades in this work. Effects of relative thickness and fixing angles of auxiliary blade on the aerodynamic performance of SB-VAWT had been analyzed in detail, which had 5 kinds of relative thickness and 3 kinds of fixing angles combined into 13 working conditions. And the main blades and the auxiliary blades were also decided as the NACA series airfoil with five kinds of relative thickness. Three kinds of fixing angle of auxiliary blade installed behind main blade were used including 0°, 5°, and 10°. The simulations included the output power coefficients, the static torque coefficients, and the flow fields around the main blade and auxiliary blade for both the dynamic and static conditions at some typical azimuth angles. The results show that the auxiliary blade with certain relative thickness and fixing angle can improve the output power characteristics and static torque characteristics of SB-VAWT, which can also provide research reference for improving the performance of VAWT.
Highlights
In recent years, with the global environmental deterioration and energy shortage becoming increasingly prominent, the research and utilization of clean and renewable energy sources have been paid more and more attention in the world
The results showed that the chord length ratio was 0.4 and the installation position of auxiliary blade was 14∘ behind the main blade, improving the performance of VAWTs
The output power of Straight-bladed Vertical Axis Wind Turbine (SB-VAWT) equipped with auxiliary blades is improved generally for Working condition A (WCA)
Summary
With the global environmental deterioration and energy shortage becoming increasingly prominent, the research and utilization of clean and renewable energy sources have been paid more and more attention in the world. The Horizontal Axis Wind Turbine (HAWT) is still the popular type in this field, another important type of wind turbines, the Straight-bladed Vertical Axis Wind Turbine (SBVAWT), has received more and more attention by researchers recently [5]. To improve the aerodynamic characteristics of SB-VAWT, some methods were proposed by researches including adding some drag type wind turbine into the rotor, installing wind gathering device around the rotor, and inventing new blade airfoil and improving the flow field around blade at larger attack angles [9,10,11]. Based on the past researches, it is known that flow fields around blades and rotor are rather complex with large vortex and separation during blade rotation process
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
