Ahmad Sedaghat, Innovative Design of New Generation of Horizontal Axis Wind Turbines (HAWT), Iran Wind Energy Conference ((IWEC2012), October 9 & 10, 2012.
Innovative Design of New Generation of Horizontal Axis Wind Turbines (HAWT)
Department of Mechanical Engineering, Isfahan University of Technology, Isfahan 84156-83111, Iran
Keywords: Wind turbine, Aerodynamics design, Blade element momentum theory.
A new innovative method for aerodynamic design of HAWT is introduced here. Aerodynamic design of horizontal axis wind turbines is presently obtained using the combined momentum and blade element theory (BEM). Further improvements were achieved by incorporating wake rotation, tip losses, and some off-design amendments. In all of these, no closed analytical solutions exist, drag coefficient is always taken to be zero when calculating axial and angular induction factors, and some cumbersome iterative numerical methods are employed to obtain wind turbine parameters. The iterative methods usually exhibit poor convergence and also sometimes lead to non-unique multiple solutions. In our new analytical approach, the mentioned theories are advanced into a new level of closed form unique solution in which all the effects of drag coefficient, wake rotation, and tip losses are incorporated for the design of new generation of HAWT. It is observed from this study that the classical optimum Glauert type wind turbines are not necessarily the best initial design; because some modification to the near root of HAWT blades introduced in our modelling can substantially enhance characteristics and performance of HAWTs particularly at high wind speeds.