Investigation on Performance Influence of Maximum Thickness Position on Vertical Axis Wind Turbine Airfoil

Abstract

Airfoil geometric configuration is very important for aerodynamic performance of a straight-bladed vertical axis wind turbine (SB-VAWT). In recent study, Islam et al have pointed out old NACA-4 are not perfectly suited for SB-VAWT operating at low Reynolds number and special purpose airfoils is needed. Islam has singled out four required geometric features which would be suitable for SB-VAWT airfoil. However, the maximum thickness position, considered one of the important geometric parameters, was not involved in Islam's research. In this paper, NACA0015 airfoil was chosen as the basic airfoil, whose maximum thickness position was shifted to generate another four airfoils. With the approach of combining XFLR5 program and Viterna-Corrignan psot-stall mode, airfoil characteristics in attack angle range from 0 degree to 90 degree have been calculated. It has been found in this paper that, with the Reynolds number changing from 50,000 to 500,000, altering the maximum thickness position has varying degrees of affects on airfoil aerodynamic characteristics. The maximum thickness position should be involved in the SB-VAWT airfoil design, and the optimum maximum thickness position needs to be determined with the consideration of the Reynolds number range where the SB-VAWT operates.

Numerical Analysis of a Modefid Airfoil for Wind Turbine

“…The airfoils with different shapes and sizes had different lift and drag force, so nondimensional lift coefficient and drag coefficient were used usually to explore the pros and cons of airfoils [4]. The Figures (4) and (5) show the results of lift coefficient and drag coefficient for NACA4412 and TCB6612, respectively, which are carried out by FLUENT.…”

“…From these results, it can be found that the value of lift coefficient is increased about 17.7%. Figure (5) shows the drag coefficient of the NACA4412 is 0.00095 while the drag coefficient of TCB6612 is 0.001.…”

“…The relationship between the power coefficient (Cp) and the tip speed ratio (λ) for a wind turbine rotor using two airfoils, NACA4412 and TCB6612, is calculated by equations (2)(3)(4)(5).…”

“…There have been a many researchers interesting in the investigation, modification, and examination of wind turbine airfoil. Qu et al [5] conducted the performance influence of maximum thickness position on vertical axis wind turbine airfoil. NACA0015 airfoil was chosen as the basic airfoil, whose maximum thickness position was shifted to generate another four airfoils, with using XFLR5 program.…”

Determine Aerodynamic Characteristics for FX63-137 Aerofoil by Using Subsonic Wind Tunnel

“…At a small angle of attack, the stagnation point is the point at which the particles of air slowing down and at which they are divided into two, which are divided into two parts of surface. Figure 2.2 shows the streamline division produced from an increase of velocity at the upper surface, while the velocity decreases at the lower surface [3].…”