A NEW APPROACH TO IMPROVE THE PERFORMANCE OF AN EXISTING SMALL WIND TURBINE BY USING DIFFUSER

Abstract

For the last few years a great deal of research work has been done in the field of wind energy to improve the performance of small wind turbines for domestic application. In this paper, a new approach of wind turbine is discussed. A new wind turbine system is developed that consists of a diffuser shroud with a broad-ring brim at the exit periphery and a small wind turbine inside it. Here, the improved effects of diffuser had on the overall performance of a small wind turbine system been studied. Besides, the effect of the diffuser shape had on the wind speed was analyzed by experimental setup and found that the wind speed in the diffuser was greatly influenced by the diffuser open angle, flange height, hub ratio, center body length, and inlet shroud shape and so on. The wind speed is increased near the inlet region of the shrouded diffuser. As a result, the output power co-efficient was increased remarkably by a factor of 2.5 to 3 times than that of a conventional wind turbine usually achieved in the field experiment

Keywords

• Wind turbine, Shroud and Brim, Static pressure co-efficient, Power co-efficient

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