Improving Vertical Axis Wind Turbine Feasibility: Predicting Turbine Airfoil Performance Via Wind Tunnel Experimentation
Vertical-axis wind turbines have a unique advantage over traditional horizontal-axis wind turbines, because they can operate at lower wind speeds. These wind speeds are typically encountered during a majority of days in the Midwest region of the United States, as well as other locations in the world. Vertical-axis wind turbine configurations have some significant advantages over horizontal-axis wind turbines. One major advantage is their size, they are small enough that they can be used in a more densely populated urban area; however, performance challenges prevent these vertical configurations from being widely integrated. One possible design solution is a spherical vertical axis turbine, employing a sequence of airfoils on the struts comprising the sphere. The objective of this research is to measure and assess the aerodynamic properties of different airfoils and predict their performance through one complete rotation. Kent State University's subsonic wind tunnel was utilized to collect the airfoil data on two airfoil shapes: the NACA 0012 and NACA 2412, at two low-speed Reynolds-numbers: 50,000 and 100,000. Conventional correction factors and curve-fitting techniques are applied to the experimental data. Using the resulting data, the optimal airfoil placements can be predicted to create a working model for further testing and implications. It is expected that the results of these experiments will assist in improving the performance of vertical-axis wind turbine configurations over a wide range of wind speeds, thus expanding the operational feasibility envelope of wind turbines as important sources of renewable energy.
Bihn, Sydney E.; Fertig, Adam J.; and Stringer, D. Blake(2019). Improving Vertical Axis Wind Turbine Feasibility: Predicting Turbine Airfoil Performance Via Wind Tunnel Experimentation. Environmental Science & Design Research Initiative. Paper 4.