Performance Improvement of Small Scale Vertical Axis Savonius Type Wind Turbine

Abstract

From last three decades, energy and environmental conservation have become a highlighted newlineresearch point for the scientists. Harnessing renewable energy is one of a viable solution to newlinecombat fossil fuel use because use of fossil fuel is a major contributor of air pollution. Wind newlineenergy is a type of renewable energy which has a huge potential to provide required power to newlinehuman being. Wind energy is developed by two types of wind turbines i.e., vertical axis wind newlineturbine (VAWT) and horizontal axis wind turbine (HAWT). For utilizing wind energy, newlinehorizontal axis wind turbine is a commonly used machine. The use of VAWTs is not common newlinedue to their poor efficiency compared to HAWTs. The researches in the direction of newlineperformance improvement VAWTs by various methods have been enhanced in recent years. newlineSavonius turbine is a VAWT with a potential of harnessing ample amount of wind energy. It is newlineobserved that, the power and torque coefficients of Savonius turbine can be improved by two newlineways i.e., by flow augmentation and negative torque reduction. The present research is to newlinedevelop, test and compare two types of modified Savonius for negative torque reduction and newlineflow augmentation. For modifications, the two turbines were equipped with different self- newlineadjusting cylindrical cowlings i.e., CC1 and CC2. The CC1 had covering angle of 180º while newlineCC2 had covering angle of 270º. The experiment was conducted by facing the rotors with wind newlineof Reynolds number range 1.06×105 1.80 ×105. newline