Abstract
In this paper, further evaluations of performances of prototype Mg-alloy micro vertical axis wind turbine were conducted. In addition, a comparative study of airfoils for vertical wind turbine was conducted; they are a prototyped airfoil based on the Clark-Y airfoil, a numerically optimized airfoil; NUT airfoil, and NACA0018 airfoil. At first, aerodynamics coefficients of lift, drag and momentum centered at the quarter of chord length at various angles of attack were clarified for those airfoils by 2-D steady CFD analysis. Typical Reynolds number were set around 3.3×10^4 for a portable-type micro VAWT system. We also examined a torque variation generated from wings with these airfoils using 3-D unsteady CFD analysis. The optimized airfoil; NUT airfoil has higher torque than NACA0018 airfoil, thus it will bring a promising improvement of power of micro VAWT.
