Study Of Leading Edge Protuberances For Low Speed Horizontal Axis Wind Turbines

Abstract

As fossil fuel reserves deplete at an ever increasing rate, renewable energy sources have become a serious alternative for power generation. Of these, Solar and Wind energy have shown a lot of promise. Wind energy is commercially and operationally the most viable renewable energy resource and is emerging as one of the largest source. While conventional wind power generation is confined to windy regions, newer blade designs are making low wind power generation increasingly effective. Wind energy will witness abundant opportunities in the developing economies such as India, where the power supply situation and infrastructure development efforts provide a huge market for active investment. Presently, Wind energy harnessing methods are limited to Horizontal Axis Wind turbines (HAWT) and Vertical axis wind turbines (VAWT).

Present workdeals with the effect of protuberances on leading edge of HAWTblade. Plain static blades incorporating the Selig/Giguere SG6043 wind turbine aero foilprofile with a uniform chord length is selected for the purpose. The protuberances are modeled as sinusoids. The amplitudes and wavelengths of the sinusoids are taken to be linear function of chord length and subsequently, the equations of the sinusoids are obtained. Five static blade models are considered for the analysis. The one free of any protuberance was taken as the baseline modeland the remaining four incorporatedsinusoidal protuberances of varying amplitude and wavelength.

Experiments were performed for varying angle of attacks to obtain lift/drag coefficients. Results indicate that the blades incorporating sinusoidal protuberances perform better in the stall regionas compared to the baseline model.This suggest that protuberant blades maybe be put to use in suitable low Reynolds number applications.