Performance Analysis of Flexible-Bladed Vertical-Axis Wind Turbines

In this study, airfoil lift and drag coefficient data are used in a blade element momentum theory-based double multiple stream tube (DMST) model to assess performance of a chord-wise flexible vertical-axis wind turbine (VAWT). Wind-tunnel experiments are performed for rigid and flexible airfoils, over a range of Reynolds numbers, and performance improvements in terms of lift and drag coefficients are discussed. Airfoil simulations are performed using the OpenFOAM framework to help identify any mechanisms of airfoil performance improvement. Finally, airfoil lift and drag data are used with the aforementioned DMST model to investigate any performance improvements in VAWT performance through the use of flexible blades.