Investigating blade performance of small horizontal axis wind turbine based on blade element momentum theory

The focus of most low wind turbine designers is how to maximize power extraction. Designing horizontal axis turbine for relatively low average wind speed requires power extraction at high tip speed ratio obtained at high angle of attack. These high angles occur at low Reynolds numbers which makes it even more difficult to generate sufficient lift to turn the blades. Therefore, the shape of the rotor blade is very important in determining the overall aerodynamic performance of the turbine. In this work, the blade element momentum theory is developed to automate the complete procedure. Three airfoils are taken for the comparative calculation of elemental power and thrust coefficient and other parameters such as circulation, torque and thrust distribution. The result is compared to experimental result for code validation. The goal is to contribute in predicting the performance of wind turbine blades and narrow down choices of airfoil in low speed regions.